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Why is there a cosmic speed limit? It could even be why we're here

Nothing in the cosmos can travel faster than light speed. By distinguishing cause and effect and stopping everything happening in a jumbled mess, our existence depends on it

By Joshua Howgego

17 November 2021

Anna Bliokh/Getty Images

TIME, various wags supposedly said, is nature’s way of stopping everything happening at once. That might not be the most useful way of thinking about things, however, not least given our confusion about how time works (see “ Why does time only move forwards? “). Take a long, hard look at physics today and it isn’t time that stops everything happening at once – it is light.

The idea that light always travels at the same speed, and that nothing can travel faster than that, is hard-baked into modern physics. It is still difficult to get your head around the mind-boggling consequences. Think of travelling in a spaceship with the beam of your headlights zinging off in front of you into the vacuum of space. A stationary observer outside your ship would see those photons travelling at light speed – 299,792,458 metres per second, for those taking notes. The crux is that so would you, no matter how fast your ship was travelling in the same direction.

Read more: 13 of the most profound questions about the cosmos and ourselves

According to Albert Einstein’s theories of relativity, which he developed in the early years of the 20th century, space and time themselves warp to accommodate the otherwise insurmountable contradictions that arise from light’s absolute speed.

His special theory of relativity gives a mathematical explanation for the cosmic speed cap: as objects with mass accelerate to higher speeds , they require more and more energy to keep them accelerating. To attain light speed, you need infinite energy – an impossibility. Light only gets a free pass as it has no mass, as…

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Faster-than -light travel: are we there yet?

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Long before the Empire struck back, before the United Federation of Planets federated, Isaac Asimov created Foundation , the epic tale of the decline and fall of the Galactic Empire. Asimov’s Empire comprised 25 million planets, knit together by sleek spaceships hurtling through the galaxy.

And how did these spaceships cross the vast gulf between the stars? By jumping through hyperspace, of course, as Asimov himself explains in Foundation:

Travel through ordinary space could proceed at no rate more rapid than that of ordinary light… and that would have meant years of travel between even the nearest of inhabited systems. Through hyper-space, that unimaginable region that was neither space nor time, matter nor energy, something nor nothing, one could traverse the length of the Galaxy in the interval between two neighboring instants of time.

What the heck is Asimov talking about? Did he know something about a secret theory of faster-than-light travel? Hardly. Asimov was participating in a grand science fiction tradition: when confronted with an immovable obstacle to your story, make something up.

You can’t beat the speed of light

The problem is that as far as we know, faster-than-light travel is impossible, making galactic empires, federations, confederacies and any other cross-galaxy civilizations impossible. But that’s so inconvenient . To evade the cosmic speed limit science fiction has created “warp-drives,” “hyperspace,” “subspace,” and other tricks that have become so ingrained, fans of science fiction don’t give them a second thought.

Everyone knows what the Enterprise is doing when it does this:

Or when the Millennium Falcon does this:

Or when the Jupiter 2… actually the Robinson family tried to get to Alpha Centauri without any special effects:

No wonder they got lost in space.

Light sets the cosmic speed limit

Why can’t we really exceed the speed of light? After all, people used to talk about a “sound barrier” up until the barrier was broken. But the speed of light is a much tougher barrier to crack. When scientists developed the theory of light back in the 19th century, it came with a special puzzle: their theory seemed to show that every observer should measure the same speed for light, about 186,000 miles per second. But that means if you try to chase a beam of light, no matter how fast you move, the light beam will still fly away from you at 186,000 miles per second. And what’s even more bizarre is that if you are moving at 99% of the speed of light, and your friend is standing still, both of you will see the light moving away at exactly the same speed.

Many scientists back then didn’t really believe this odd prediction, and the American physicist Albert Michelson (along with his collaborator Edward Morley) set out to measure how the speed of light would change due to the motion of the earth through space. But their famous Michelson-Morley experiment found no change at all. The speed of light seemed to be the same regardless of whether they measured it in the same direction the earth was moving, or in some other direction – a rare example of a non-discovery that turned out to be more important than a discovery!

Enter Einstein and relativity

Instead of trying to explain away this bizarreness, Albert Einstein embraced it. He built an entire theory, called special relativity , around the idea that the speed of light is the same for everyone who measures it, no matter how fast they are moving in relation to the light. In order to accommodate this behavior for light, Einstein’s theory predicted that time and space would have to stretch or contract as someone traveled with increasing speed. And out of special relativity popped a cosmic speed limit: nothing could ever exceed the speed of light.

Relativity is a cornerstone of all of modern physics, and we have no reason to doubt it – no one has ever observed an object moving faster than light. There’s actually a minor clarification necessary here: Einstein’s speed limit is the speed of light in a vacuum . Light slows down when it moves through a material like water or glass, and then it’s perfectly possible to exceed this reduced speed of light – up to its speed in a vacuum, of course. Anything moving faster than light in water or glass produces the luminous equivalent of a sonic boom, called Čerenkov radiation. It’s what gives underwater nuclear reactors their attractive blue glow.

But about that warp drive…

Of all of the attempts to wiggle out of Einstein’s speed limit, probably the most plausible is theoretical physicist Miguel Alcubierre’s “warp drive” . Alcubierre’s proposal doesn’t violate the cosmic speed limit – it goes around it. Try filling a greasy frying pan with water and then put a drop of soap into the pan. The grease will fly away to the sides of the pan.

Alcubierre’s warp drive does the same thing with space itself . Alcubierre showed that by a suitable distribution of matter, you can shrink space in front of your spaceship and stretch it behind the spaceship, creating a small bubble around the ship that moves as fast as you like. Because space is contracting in front of the ship, the ship wouldn’t officially be moving faster than the speed of light. In fact, the ship would actually be at rest relative to the warp bubble, and the people inside the ship wouldn’t even feel any acceleration. Talk about a smooth ride!

There’s just one tiny problem…. Alcubierre’s space warp can only be generated by violating something called the “weak energy condition.” Scientists can’t prove that the weak energy condition is always true, but any violation would produce a lot of strange things, like negative energy densities, and possible wormholes or time machines . Cool – sign me up for that! But we’ve never seen any actual violations of the weak energy condition. So the Alcubierre warp drive occupies a kind of physics twilight zone – not absolutely ruled out, but not very plausible, either.

So how will humanity ever reach the stars? The door marked “faster-than-light travel” has been slammed in our face and welded shut. We’ll have to sneak in some other way. Get to work!

• Space travel
• Special Relativity
• Speed of light

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Warp Drives and Negative Energy: Physicists Give Chances of Faster-Than-Light Space Travel a Boost

By Mario Borunda, Oklahoma State University May 16, 2021

Faster than light travel is the only way humans could ever get to other stars in a reasonable amount of time. Credit: NASA

The closest star to Earth is Proxima Centauri. It is about 4.25 light-years away, or about 25 trillion miles (40 trillion km). The fastest ever spacecraft, the now-in-space Parker Solar Probe will reach a top speed of 450,000 mph (201 km/s). It would take just 20 seconds to go from Los Angeles to New York City at that speed, but it would take the solar probe about 6,633 years to reach Earth’s nearest neighboring solar system.

If humanity ever wants to travel easily between stars, people will need to go faster than light. But so far, faster-than-light travel is possible only in science fiction.

In Issac Asimov’s Foundation series, humanity can travel from planet to planet, star to star or across the universe using jump drives. As a kid, I read as many of those stories as I could get my hands on. I am now a theoretical physicist and study nanotechnology, but I am still fascinated by the ways humanity could one day travel in space.

Some characters – like the astronauts in the movies “Interstellar” and “Thor” – use wormholes to travel between solar systems in seconds. Another approach – familiar to “Star Trek” fans – is warp drive technology. Warp drives are theoretically possible if still far-fetched technology. Two recent papers made headlines in March when researchers claimed to have overcome one of the many challenges that stand between the theory of warp drives and reality.

But how do these theoretical warp drives really work? And will humans be making the jump to warp speed anytime soon?

This 2-dimensional representation shows the flat, unwarped bubble of spacetime in the center where a warp drive would sit surrounded by compressed spacetime to the right (downward curve) and expanded spacetime to the left (upward curve). Credit: AllenMcC/Wikimedia Commons

Compression and expansion

Physicists’ current understanding of spacetime comes from Albert Einstein’s theory of General Relativity. General Relativity states that space and time are fused and that nothing can travel faster than the speed of light. General relativity also describes how mass and energy warp spacetime – hefty objects like stars and black holes curve spacetime around them. This curvature is what you feel as gravity and why many spacefaring heroes worry about “getting stuck in” or “falling into” a gravity well. Early science fiction writers John Campbell and Asimov saw this warping as a way to skirt the speed limit.

What if a starship could compress space in front of it while expanding spacetime behind it? “Star Trek” took this idea and named it the warp drive.

In 1994, Miguel Alcubierre, a Mexican theoretical physicist, showed that compressing spacetime in front of the spaceship while expanding it behind was mathematically possible within the laws of General Relativity . So, what does that mean? Imagine the distance between two points is 10 meters (33 feet). If you are standing at point A and can travel one meter per second, it would take 10 seconds to get to point B. However, let’s say you could somehow compress the space between you and point B so that the interval is now just one meter. Then, moving through spacetime at your maximum speed of one meter per second, you would be able to reach point B in about one second. In theory, this approach does not contradict the laws of relativity since you are not moving faster than light in the space around you. Alcubierre showed that the warp drive from “Star Trek” was in fact theoretically possible.

Proxima Centauri here we come, right? Unfortunately, Alcubierre’s method of compressing spacetime had one problem: it requires negative energy or negative mass.

This 2–dimensional representation shows how positive mass curves spacetime (left side, blue earth) and negative mass curves spacetime in an opposite direction (right side, red earth). Credit: Tokamac/Wikimedia Commons, CC BY-SA

A negative energy problem

Alcubierre’s warp drive would work by creating a bubble of flat spacetime around the spaceship and curving spacetime around that bubble to reduce distances. The warp drive would require either negative mass – a theorized type of matter – or a ring of negative energy density to work. Physicists have never observed negative mass, so that leaves negative energy as the only option.

To create negative energy, a warp drive would use a huge amount of mass to create an imbalance between particles and antiparticles. For example, if an electron and an antielectron appear near the warp drive, one of the particles would get trapped by the mass and this results in an imbalance. This imbalance results in negative energy density. Alcubierre’s warp drive would use this negative energy to create the spacetime bubble.

But for a warp drive to generate enough negative energy, you would need a lot of matter. Alcubierre estimated that a warp drive with a 100-meter bubble would require the mass of the entire visible universe .

In 1999, physicist Chris Van Den Broeck showed that expanding the volume inside the bubble but keeping the surface area constant would reduce the energy requirements significantly , to just about the mass of the sun. A significant improvement, but still far beyond all practical possibilities.

A sci-fi future?

Two recent papers – one by Alexey Bobrick and Gianni Martire and another by Erik Lentz – provide solutions that seem to bring warp drives closer to reality.

Bobrick and Martire realized that by modifying spacetime within the bubble in a certain way, they could remove the need to use negative energy. This solution, though, does not produce a warp drive that can go faster than light.

Independently, Lentz also proposed a solution that does not require negative energy. He used a different geometric approach to solve the equations of General Relativity, and by doing so, he found that a warp drive wouldn’t need to use negative energy. Lentz’s solution would allow the bubble to travel faster than the speed of light.

It is essential to point out that these exciting developments are mathematical models. As a physicist, I won’t fully trust models until we have experimental proof. Yet, the science of warp drives is coming into view. As a science fiction fan, I welcome all this innovative thinking. In the words of Captain Picard , things are only impossible until they are not.

Written by Mario Borunda, Associate Professor of Physics, Oklahoma State University.

Adapted from an article originally published on The Conversation .

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The battle of the covid variants: a winning approach, 27 comments on "warp drives and negative energy: physicists give chances of faster-than-light space travel a boost".

Chinese Logicians School and their paradoxes aside for the time being: Even though it’s white, has wings and it’s name is Pegasus, it’s still a horse. It cannot fly and is as dead as the Mythology that spawned it. A dead horse is not a horse. Beat it all you want, it’s a deadhorse. Subtle Logic. Essentials and Essential Quality (Whiteness and Horse-ness) define a beast of a different color. Light is not a speed limit if everything is moving at the speed of light. It is more like a bullet fired off the trailing end of a speeding train. You can’t see it until it hits something… like your retina. The problem begins in the occipital lobe and migrates frontally. From there, it is only a matter of TIME… and the MANIFOLD UNIVERSE of the MIND: IT is all in how one looks at it.

Now… Back to the telescope and a cup of hot chocolate. Here’s looking at you. ☝️

Wow, that’s some deep brown matter, Alex, and I don’t mean the coffee.

Well… We ARE immersed in a wealth of brown matter. Orthodoxy notwithstanding, one can science the heck out of it, but it is a meaningless WASTE of human resources when misdirected: particularly when it is EXPENSIVE. It’s in the GREY MATTER, ultimately, the biases that allow us to poison our “home” planet on the promise of finding another one JUST LIKE IT. Good luck with that: not in a hundred lifetimes, even @ the speed o’ lite. To wit: Whatever we might aim our Lightships at, ISN’T THERE ANYMORE. WARP NINE, MUSTER WARF. MAKE IT SO. LOL What I was suggesting was a paradigm (that word) SHIFT. Ya know, like… maybe stand still, RELATIVELY SPEAKING, while Space moves past us. Forget about TIME for the time being. There is no way “around” it, but maybe there is a way outside of it. Some theorists are pursuing this line of reasoning. I have been “educated” to an insight: The solution is much simpler than our Science can imagine; as vested as it is in misconceptions about this ONE Universe, that belong in the Middle (muddle?) Ages, along with witches, goblins, the homunculus, god, seven days in the week and a paradigm of EXISTENCE hopelessly mired in its obsession with mortality and bodily functions; which is still trying to turn lead into gold, but fails at differentiating SH*T FROM SHINOLA. Call me IDEALISTIC… and I will correct your thinking. REALISTICALLY speaking, Pangloss, I GUESS was correct: We live in the BEST if all possible WORLDS…I have some land in Florida for sale. Real cheap. It only under water twice a day.

It’s not brain surgery.

BTW, I was drinking hot chocolate; a suggestion of a neurosurgeon friend who drinks it during prolonged surgeries (+6 hours). It contains a better form of caffeine than coffee; one that does not rattle the nerves. With the “work” he does, one little tremor and ZIP! there goes your memory of Aunt Tilly, or maybe just the memory of how to tie your own shoelaces…

👽 Keep looking up. ☝️

Why did you take out my comment on Dr. Lee and Synthetic Gravity demonstrated in Huntsville, Alabama in 1998? I realize the program went black, i.e., Beyond Top Secret and thus was scrubbed from the Internet by the year 2000.

Quantum information travels faster than light, so that is what everyone else in the universe exploits to travel to the stars. Quantum Tunneling Vehicles (QTV). They emulate an elementary particle by spinning a strong electric or magnetic field around a superconducting hull to engage a particle spreadsheet function. Altering and renormalizing the spin of the field should cause the universe to re-locate the ersatz particle. It’s a form of quantum teleportation, if you mess with the constancy of the spin field, you can trick the universe into changing it’s location. Electric tunneling vehicles would be oblate spheroids, magnetic tunneling vehicles would be cigar shaped. Classic UFO’s, saucers and cigars. Why don’t we just follow their lead? Or are we stupid cavemen who need rockets to fly through space? Classical physics has a speed limit, the speed of light. If you want to beat it safely, you have to play the quantum game instead. Fortunately, quantum information travels faster than light. Quantum laws govern the conservation laws, which are monitored on every particle in the universe at once. So if I can con the universe into thinking my ship is an elementary particle and that my “particle” belongs somewhere else, I’ll instantly find my “particle” there. The quantum machinery of reality is not subject to the limitations of the classical laws it emulates. The closest stars may be only hours or minutes away to a sophisticated Quantum Tunneling Vehicle. And if you need a lift vehicle that can hit orbit 20 rimes a day with no pollution, or go to Mars in minutes, all we need are room temperature superconductors and a lot of electricity.

You have something there. Generating a strong enough field will effectively create a “bubble” around which Time and Space will flow…at the Speed of light and beyond, as the “vector” of “flight” shortens in response to Space/Time distortion… Only a Theory. But it beats the Wile E. Coyote, strap a rocket to your ass, school of space travel. As in any Scientific theorising, the first SPACE one needs to overcome is the space between one’s ears. It is, after all, the Final Frontier.

Babu G. Ranganathan* (B.A. Bible/Biology)

JUST BECAUSE SCIENCE CAN EXPLAIN how an airplane works doesn’t mean that no one designed or made the airplane. And just because science can explain how life or the universe works doesn’t mean there was no Designer and Maker behind them.

Natural laws may explain how the order in the universe works and operates, but mere undirected natural laws cannot explain the origin of that order. Once you have a complete and living cell then the genetic code and biological machinery exist to direct the formation of more cells from raw materials such as amino acids and other chemicals, but how could life or the cell have naturally originated when no directing code and mechanisms existed in nature? Read my Internet article: HOW FORENSIC SCIENCE REFUTES ATHEISM.

WHAT IS SCIENCE? Science simply is knowledge based on observation. No human observed the universe coming by chance or by design, by creation or by evolution. These are positions of faith. The issue is which faith the scientific evidence best supports.

SCIENCE SHOWS THAT THE UNIVERSE CANNOT BE ETERNAL because it could not have sustained itself eternally due to the law of entropy (increasing and irreversible net energy decay, even in an open system). Even a hypothetical oscillating universe could not continue to oscillate eternally! Einstein’s General Theory of Relativity shows that space, matter, and time all are physical and all had a beginning. Space even produces particles because it’s actually something, not nothing. What about the Higgs boson (the so-called “God Particle”)? The Higgs boson, even if it existed, would not have created mass from nothing, but rather it would have converted energy into mass. Einstein showed that all matter is some form of energy. Even time had a beginning! Time is not eternal.

The law of entropy doesn’t allow the universe to be eternal. If the universe were eternal, everything, including time (which modern science has shown is as physical as mass and space), would have become totally entropied by now and the entire universe would have ended in a uniform heat death a long, long time ago. The fact that this hasn’t happened already is powerful evidence for a beginning to the universe.

Popular atheistic scientist Stephen Hawking admits that the universe had a beginning and came from nothing but he believes that nothing became something by a natural process yet to be discovered. That’s not rational thinking at all, and it also would be making the effect greater than its cause to say that nothing created something. The beginning had to be of supernatural origin because science teaches us from the First Law of Thermodynamics that natural laws and processes do not have the ability to bring something into existence from nothing.

The supernatural origin of the universe cannot be proved by science but science points to a supernatural intelligence and power for the origin and order of the universe. Where did God come from? Obviously, unlike the universe, God’s nature doesn’t require a beginning.

The disorder in the universe can be explained because of chance and random processes, but the order can be explained only because of intelligence and design.

Gravity may explain how the order found in the precise and orderly courses of thousands of billions of stars is maintained, but gravity cannot explain the origin of that order.

Some evolutionary astronomers believe that trillions of stars crashed into each other leaving surviving stars to find precise orderly orbits in space. Not only is this irrational, but if there was such a mass collision of stars then there would be a super mass residue of gas clouds in space to support this hypothesis. The present level of residue of gas clouds in space doesn’t support the magnitude of star deaths required for such a hypothesis. And, as already stated, the origin of stars cannot be explained by the Big Bang because of the reasons mentioned above. It’s one thing to say that stars may decay and die into random gas clouds, but it is totally different to say that gas clouds form into stars.

Even the father of Chaos theory admitted that the “mechanisms” existing in the non-living world allow for only very rudimentary levels of order to arise spontaneously (by chance), but not the kind or level of order we find in the structures of DNA, RNA, and proteins. Yes, individual amino acids have been shown to come into existence by chance but not protein molecules which require that the various amino acids be in a precise sequence just like the letters found in a sentence.

Some things don’t need experiment or scientific proof. In law there is a dictum called prima facie evidence. It means “evidence that speaks for itself.”

An example of a true prima facie would be if you discovered an elaborate sand castle on the beach. You don’t have to experiment to know that it came by design and not by the chance forces of wind and water.

If you discovered a romantic letter or message written in the sand, you don’t have to experiment to know that it was by design and not because a stick randomly carried by wind put it there. You naturally assume that an intelligent and rational being was responsible.

It’s interesting that Carl Sagan would have acknowledged sequential radio signals in space as evidence of intelligent life sending them, but he wouldn’t acknowledge the sequential structure of molecules in DNA (the genetic code) as evidence of an intelligent Cause. Read my popular Internet article, HOW DID MY DNA MAKE ME.

I encourage all to read my popular Internet articles:

NATURAL LIMITS TO EVOLUTION HOW FORENSIC SCIENCE REFUTES ATHEISM

Visit my latest Internet site: THE SCIENCE SUPPORTING CREATION (This site answers many arguments, both old and new, that have been used by evolutionists to support their theory)

Author of popular Internet article, TRADITIONAL DOCTRINE OF HELL EVOLVED FROM GREEK ROOTS

*I have given successful lectures (with question and answer period afterwards) defending creation before evolutionist science faculty and students at various colleges and universities. I’ve been privileged to be recognized in the 24th edition of Marquis “Who’s Who in The East” for my writings on religion and science.

Strong is the wind that blows…

We should continue to search, yet it seems to me more effort is and should be placed on inner planetary travel. Nuclear rocket engines or even better fusion drive with impulses reaching 30,000 mps would open the planets and mining of asteroids. This would reduce travel time and fuel consumption making the inner planets give up their secrets and spread out mankind against catastrophe. I would love to travel to proxima centaury in what’s left of my life, it’s not going to happen. That’s why we have science fiction stories!

Warp drives and negative energy…either reduce mass beyond zero or…maybe a large time difference.. bubble with large time difference like helium vs. air…or tuning a radio to a different frequency than the natural surrounding space?

The way that the Star Trek’s warp dive works is that the Antimatter is stored because it needs a smaller area to contain it in a magnetic field. The Nacelles in the front is what collects the matter. They are called Bussard Collector. It then goes to a Dilithium Chamber where the Dilithium Crystals are. The matter and antimatter enters the chamber and instead of a violent explosion the Dilithium controls the explosion and is converted to warp plasma. The plasma then goes back to the nacelle where the Warp Plasma Coils are and creates the warp bubble and then bends the space in front of the ship.

SpaceTime idea seems like a 2D model. Living on Earth is a kind of gravity well that’s why we need massive energy to escape it pull down. I don’t but the ‘spacetime’ idea. Space is relative emptiness. Time is a measure of movement.

Thus far humans have been thinking of REpulsion methods of travel. Pretty much male thinking. But say you want to go towards a female, you can use ‘push’ but most importantly ‘pull’ method; ie: attraction A combination of pull(attraction) and push(repulsion) would work better.

Think of a plant. How does it grow towards the light? It produces a substance that captures and stores light energy and transfers it to the roots to push further into the soil. So a plant has a pull and push method/mechanism (ATP, is it?)

Now you want to go to another star system. Ok. Aim your light-capture device at the stars center mass. Begin light collection, storage and transfer. Expel light thru rear. This method is like using light as zipline. But what material could capture light energy, store and/or transfer it out causing the spacecraft to pull and push itself towards the destination?

Or maybe a light-attracting device in the bow and a light-repelling device in the stern. Lineup the ship between two stars and go. The bow pulls towards the destined/arrival star while the stern pushes off the source/departing star.

Another way or maybe related is a kind of lightplane that sucks in light and expells it (like an airplane). But what kind of engine & fuel would one need to suckin light, ‘combust it and expell it’?

Another idea is to run a ship on cosmic background radiation.

Think of how long it took ‘god’ to build an organism to build a telescope to see light from a distant star. Evolution got us here in about 4.5B years, right? How can we travel at the speed of imagination? We need light. Go towards the light.

1) Attract light and repel light. Photonic propulsiom? 2) Space is a relatively cold void, what cuts thru a cold void? Hot plasma? Plasma Drive? 3) Combination of engines/methods (all-in-one).

We can build and prepare for when our star goes supernova and surf that in all directions. ~4.5B years.

It makes sense that our star’s life cycle and consciousness would follow ours. At midlife, I am beginning to see what is possible and not for me. Sure I still wish and hope with imaginatiom, but time to get real. It follows that since this star made and sustains us that once its gone, so will we be. Unless perhaps if we link up to another star or to the supermassive giant star in our galactic core. And when that goes supernova we can surf that. When a star goes boom, it spreads its matter out. Its amazing enough that the star maintains a balanced fusion reaction, but that it also explodes or dies out as it loses mass. We don’t have to wait. I’m sure we can imagine something and mame it real. I mean can we even excite a particle to go at light speed? And 6k years is still shorter than waiting 4.5 billion years to be shot out like dead matter. I think we need to capture more energy from our star, concentrate it, build brains (organic & inorganic), swarm brains, augment/unify intelligence and consciousness. Maybe there is a way to recombine light coming from another star with light from our star to build particles/matter at the destined end by scanning ourselves from our end. Yes teleportation via 3D printing matter using light from destined star and energy from our star. In 4.5B years I think we can perfect this. (One issue is it might be less dense at the destined end.)

Imagination is the key; the crazier the better.

We might have to figure out a way to take our Earth mothership with us since we are wholly dependent on her ATM. Say within 4.5B years we would have been able to remake all the matter in the solar system into useful devices, basically remaking our planet & ourselves via 3D quantum plank’s length printing. Basically reshape all matter to our imagined consciousness. Priority is to extract more and more energy from our star then we’ll have more possibilities and if we figure out a hack can multiply virally throughout the galaxy increasing our chances. Seems destined and predetermimed. Energy capture & matter manipulation is key. We need sharper senses: better ‘nanoscopes’, better causal-logic processes, finer manipulation of matter, energy efficiency, more accurate theories & mathmatics…anything & everything; there is no limit to godliness.

how long would you say it would take to successfully and completely create said warp drive?

In truth, it took God one day to create the first human being without evolution. It took six days to create the whole Universe. He made us in his image, but not so that we ARE Gods, but his children. He is the God of creation, thus we should be creative, we will find a way to travel faster than the speed of light many times over.

In 2013, A group of us (named C-PLUSS) definitively proved that this proposed method for “warp drive” does not work the way that they say it works. The localised tidal-forces on space-time would be too much to bear. It can cause irreparable damage to local space-time. I have copies of our notes, our conclusions, and our recommendations for an alternative methodology to create a “warp drive”. C-PLUSS stands for the Committee to Propose Legitimate Ultra-luminal Speed Systems. I can be reached at [email protected] .

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A Groundbreaking Scientific Discovery Just Created the Instruction Manual for Light-Speed Travel

In a first for warp drives, this research actually obeys the laws of physics.

If a superluminal—meaning faster than the speed of light—warp drive like Alcubierre’s worked, it would revolutionize humanity’s endeavors across the universe , allowing us, perhaps, to reach Alpha Centauri, our closest star system, in days or weeks even though it’s four light years away.

The clip above from the 2016 film Star Trek Beyond showcases the effect of a starship zipping through space inside a faster-than-light warp bubble. You can see the imagined but hypothetically accurate warping of spacetime.

However, the Alcubierre drive has a glaring problem: the force behind its operation, called “negative energy,” involves exotic particles—hypothetical matter that, as far as we know, doesn’t exist in our universe. Described only in mathematical terms, exotic particles act in unexpected ways, like having negative mass and working in opposition to gravity (in fact, it has “anti-gravity”). For the past 30 years, scientists have been publishing research that chips away at the inherent hurdles to light speed revealed in Alcubierre’s foundational 1994 article published in the peer-reviewed journal Classical and Quantum Gravity .

Now, researchers at the New York City-based think tank Applied Physics believe they’ve found a creative new approach to solving the warp drive’s fundamental roadblock. Along with colleagues from other institutions, the team envisioned a “positive energy” system that doesn’t violate the known laws of physics . It’s a game-changer, say two of the study’s authors: Gianni Martire, CEO of Applied Physics, and Jared Fuchs, Ph.D., a senior scientist there. Their work, also published in Classical and Quantum Gravity in late April, could be the first chapter in the manual for interstellar spaceflight.

Positive energy makes all the difference. Imagine you are an astronaut in space, pushing a tennis ball away from you. Instead of moving away, the ball pushes back, to the point that it would “take your hand off” if you applied enough pushing force, Martire tells Popular Mechanics . That’s a sign of negative energy, and, though the Alcubierre drive design requires it, there’s no way to harness it.

Instead, regular old positive energy is more feasible for constructing the “ warp bubble .” As its name suggests, it’s a spherical structure that surrounds and encloses space for a passenger ship using a shell of regular—but incredibly dense—matter. The bubble propels the spaceship using the powerful gravity of the shell, but without causing the passengers to feel any acceleration. “An elevator ride would be more eventful,” Martire says.

That’s because the density of the shell, as well as the pressure it exerts on the interior, is controlled carefully, Fuchs tells Popular Mechanics . Nothing can travel faster than the speed of light, according to the gravity-bound principles of Albert Einstein’s theory of general relativity . So the bubble is designed such that observers within their local spacetime environment—inside the bubble—experience normal movement in time. Simultaneously, the bubble itself compresses the spacetime in front of the ship and expands it behind the ship, ferrying itself and the contained craft incredibly fast. The walls of the bubble generate the necessary momentum, akin to the momentum of balls rolling, Fuchs explains. “It’s the movement of the matter in the walls that actually creates the effect for passengers on the inside.”

Building on its 2021 paper published in Classical and Quantum Gravity —which details the same researchers’ earlier work on physical warp drives—the team was able to model the complexity of the system using its own computational program, Warp Factory. This toolkit for modeling warp drive spacetimes allows researchers to evaluate Einstein’s field equations and compute the energy conditions required for various warp drive geometries. Anyone can download and use it for free . These experiments led to what Fuchs calls a mini model, the first general model of a positive-energy warp drive. Their past work also demonstrated that the amount of energy a warp bubble requires depends on the shape of the bubble; for example, the flatter the bubble in the direction of travel, the less energy it needs.

☄️ DID YOU KNOW? People have been imagining traveling as fast as light for nearly a century, if not longer. The 1931 novel Islands of Space by John W. Campbell mentions a “warp” method in the context of superluminal space travel.

This latest advancement suggests fresh possibilities for studying warp travel design, Erik Lentz, Ph.D., tells Popular Mechanics . In his current position as a staff physicist at Pacific Northwest National Laboratory in Richland, Washington, Lentz contributes to research on dark matter detection and quantum information science research. His independent research in warp drive theory also aims to be grounded in conventional physics while reimagining the shape of warped space. The topic needs to overcome many practical hurdles, he says.

Controlling warp bubbles requires a great deal of coordination because they involve enormous amounts of matter and energy to keep the passengers safe and with a similar passage of time as the destination. “We could just as well engineer spacetime where time passes much differently inside [the passenger compartment] than outside. We could miss our appointment at Proxima Centauri if we aren’t careful,” Lentz says. “That is still a risk if we are traveling less than the speed of light.” Communication between people inside the bubble and outside could also become distorted as it passes through the curvature of warped space, he adds.

While Applied Physics’ current solution requires a warp drive that travels below the speed of light, the model still needs to plug in a mass equivalent to about two Jupiters. Otherwise, it will never achieve the gravitational force and momentum high enough to cause a meaningful warp effect. But no one knows what the source of this mass could be—not yet, at least. Some research suggests that if we could somehow harness dark matter , we could use it for light-speed travel, but Fuchs and Martire are doubtful, since it’s currently a big mystery (and an exotic particle).

Despite the many problems scientists still need to solve to build a working warp drive, the Applied Physics team claims its model should eventually get closer to light speed. And even if a feasible model remains below the speed of light, it’s a vast improvement over today’s technology. For example, traveling at even half the speed of light to Alpha Centauri would take nine years. In stark contrast, our fastest spacecraft, Voyager 1—currently traveling at 38,000 miles per hour—would take 75,000 years to reach our closest neighboring star system.

Of course, as you approach the actual speed of light, things get truly weird, according to the principles of Einstein’s special relativity . The mass of an object moving faster and faster would increase infinitely, eventually requiring an infinite amount of energy to maintain its speed.

“That’s the chief limitation and key challenge we have to overcome—how can we have all this matter in our [bubble], but not at such a scale that we can never even put it together?” Martire says. It’s possible the answer lies in condensed matter physics, he adds. This branch of physics deals particularly with the forces between atoms and electrons in matter. It has already proven fundamental to several of our current technologies, such as transistors, solid-state lasers, and magnetic storage media.

The other big issue is that current models allow a stable warp bubble, but only for a constant velocity. Scientists still need to figure out how to design an initial acceleration. On the other end of the journey, how will the ship slow down and stop? “It’s like trying to grasp the automobile for the first time,” Martire says. “We don’t have an engine just yet, but we see the light at the end of the tunnel.” Warp drive technology is at the stage of 1882 car technology, he says: when automobile travel was possible, but it still looked like a hard, hard problem.

The Applied Physics team believes future innovations in warp travel are inevitable. The general positive energy model is a first step. Besides, you don’t need to zoom at light speed to achieve distances that today are just a dream, Martire says. “Humanity is officially, mathematically, on an interstellar track.”

Before joining Popular Mechanics , Manasee Wagh worked as a newspaper reporter, a science journalist, a tech writer, and a computer engineer. She’s always looking for ways to combine the three greatest joys in her life: science, travel, and food.

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What is the speed of light? Here’s the history, discovery of the cosmic speed limit

On one hand, the speed of light is just a number: 299,792,458 meters per second. And on the other, it’s one of the most important constants that appears in nature and defines the relationship of causality itself.

As far as we can measure, it is a constant. It is the same speed for every observer in the entire universe. This constancy was first established in the late 1800’s with the experiments of Albert Michelson and Edward Morley at Case Western Reserve University . They attempted to measure changes in the speed of light as the Earth orbited around the Sun. They found no such variation, and no experiment ever since then has either.

Observations of the cosmic microwave background, the light released when the universe was 380,000 years old, show that the speed of light hasn’t measurably changed in over 13.8 billion years.

In fact, we now define the speed of light to be a constant, with a precise speed of 299,792,458 meters per second. While it remains a remote possibility in deeply theoretical physics that light may not be a constant, for all known purposes it is a constant, so it’s better to just define it and move on with life.

How was the speed of light first measured?

In 1676 the Danish astronomer Ole Christensen Romer made the first quantitative measurement of how fast light travels. He carefully observed the orbit of Io, the innermost moon of Jupiter. As the Earth circles the Sun in its own orbit, sometimes it approaches Jupiter and sometimes it recedes away from it. When the Earth is approaching Jupiter, the path that light has to travel from Io is shorter than when the Earth is receding away from Jupiter. By carefully measuring the changes to Io’s orbital period, Romer calculated a speed of light of around 220,000 kilometers per second.

Observations continued to improve until by the 19 th century astronomers and physicists had developed the sophistication to get very close to the modern value. In 1865, James Clerk Maxwell made a remarkable discovery. He was investigating the properties of electricity and magnetism, which for decades had remained mysterious in unconnected laboratory experiments around the world. Maxwell found that electricity and magnetism were really two sides of the same coin, both manifestations of a single electromagnetic force.

As Maxwell explored the consequences of his new theory, he found that changing magnetic fields can lead to changing electric fields, which then lead to a new round of changing magnetic fields. The fields leapfrog over each other and can even travel through empty space. When Maxwell went to calculate the speed of these electromagnetic waves, he was surprised to see the speed of light pop out – the first theoretical calculation of this important number.

What is the most precise measurement of the speed of light?

Because it is defined to be a constant, there’s no need to measure it further. The number we’ve defined is it, with no uncertainty, no error bars. It’s done. But the speed of light is just that – a speed. The number we choose to represent it depends on the units we use: kilometers versus miles, seconds versus hours, and so on. In fact, physicists commonly just set the speed of light to be 1 to make their calculations easier. So instead of trying to measure the speed light travels, physicists turn to more precisely measuring other units, like the length of the meter or the duration of the second. In other words, the defined value of the speed of light is used to establish the length of other units like the meter.

How does light slow down?

Yes, the speed of light is always a constant. But it slows down whenever it travels through a medium like air or water. How does this work? There are a few different ways to present an answer to this question, depending on whether you prefer a particle-like picture or a wave-like picture.

In a particle-like picture, light is made of tiny little bullets called photons. All those photons always travel at the speed of light, but as light passes through a medium those photons get all tangled up, bouncing around among all the molecules of the medium. This slows down the overall propagation of light, because it takes more time for the group of photons to make it through.

In a wave-like picture, light is made of electromagnetic waves. When these waves pass through a medium, they get all the charged particles in motion, which in turn generate new electromagnetic waves of their own. These interfere with the original light, forcing it to slow down as it passes through.

Either way, light always travels at the same speed, but matter can interfere with its travel, making it slow down.

Why is the speed of light important?

The speed of light is important because it’s about way more than, well, the speed of light. In the early 1900’s Einstein realized just how special this speed is. The old physics, dominated by the work of Isaac Newton, said that the universe had a fixed reference frame from which we could measure all motion. This is why Michelson and Morley went looking for changes in the speed, because it should change depending on our point of view. But their experiments showed that the speed was always constant, so what gives?

Einstein decided to take this experiment at face value. He assumed that the speed of light is a true, fundamental constant. No matter where you are, no matter how fast you’re moving, you’ll always see the same speed.

This is wild to think about. If you’re traveling at 99% the speed of light and turn on a flashlight, the beam will race ahead of you at…exactly the speed of light, no more, no less. If you’re coming from the opposite direction, you’ll still also measure the exact same speed.

This constancy forms the basis of Einstein’s special theory of relativity, which tells us that while all motion is relative – different observers won’t always agree on the length of measurements or the duration of events – some things are truly universal, like the speed of light.

Can you go faster than light speed?

Nope. Nothing can. Any particle with zero mass must travel at light speed. But anything with mass (which is most of the universe) cannot. The problem is relativity. The faster you go, the more energy you have. But we know from Einstein’s relativity that energy and mass are the same thing. So the more energy you have, the more mass you have, which makes it harder for you to go even faster. You can get as close as you want to the speed of light, but to actually crack that barrier takes an infinite amount of energy. So don’t even try.

How is the speed at which light travels related to causality?

If you think you can find a cheat to get around the limitations of light speed, then I need to tell you about its role in special relativity. You see, it’s not just about light. It just so happens that light travels at this special speed, and it was the first thing we discovered to travel at this speed. So it could have had another name. Indeed, a better name for this speed might be “the speed of time.”

Related: Is time travel possible? An astrophysicist explains

We live in a universe of causes and effects. All effects are preceded by a cause, and all causes lead to effects. The speed of light limits how quickly causes can lead to effects. Because it’s a maximum speed limit for any motion or interaction, in a given amount of time there’s a limit to what I can influence. If I want to tap you on the shoulder and you’re right next to me, I can do it right away. But if you’re on the other side of the planet, I have to travel there first. The motion of me traveling to you is limited by the speed of light, so that sets how quickly I can tap you on the shoulder – the speed light travels dictates how quickly a single cause can create an effect.

The ability to go faster than light would allow effects to happen before their causes. In essence, time travel into the past would be possible with faster-than-light travel. Since we view time as the unbroken chain of causes and effects going from the past to the future, breaking the speed of light would break causality, which would seriously undermine our sense of the forward motion of time.

Why does light travel at this speed?

No clue. It appears to us as a fundamental constant of nature. We have no theory of physics that explains its existence or why it has the value that it does. We hope that a future understanding of nature will provide this explanation, but right now all investigations are purely theoretical. For now, we just have to take it as a given.

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Why is the speed of light the way it is?

It's just plain weird.

Paul M. Sutter is an astrophysicist at SUNY Stony Brook and the Flatiron Institute, host of Ask a Spaceman and Space Radio , and author of " How to Die in Space ." He contributed this article to Space.com's Expert Voices: Op-Ed & Insights . 

We all know and love the speed of light — 299,792,458 meters per second — but why does it have the value that it does? Why isn't it some other number? And why do we care so much about some random speed of electromagnetic waves? Why did it become such a cornerstone of physics? 

Well, it's because the speed of light is just plain weird.

Related: Constant speed of light: Einstein's special relativity survives a high-energy test

Putting light to the test

The first person to realize that light does indeed have a speed at all was an astronomer by the name of Ole Romer. In the late 1600s, he was obsessed with some strange motions of the moon Io around Jupiter. Every once in a while, the great planet would block our view of its little moon, causing an eclipse, but the timing between eclipses seemed to change over the course of the year. Either something funky was happening with the orbit of Io — which seemed suspicious — or something else was afoot.

After a couple years of observations, Romer made the connection. When we see Io get eclipsed, we're in a certain position in our own orbit around the sun. But by the next time we see another eclipse, a few days later, we're in a slightly different position, maybe closer or farther away from Jupiter than the last time. If we are farther away than the last time we saw an eclipse, then that means we have to wait a little bit of extra time to see the next one because it takes that much longer for the light to reach us, and the reverse is true if we happen to be a little bit closer to Jupiter.

The only way to explain the variations in the timing of eclipses of Io is if light has a finite speed.

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Making it mean something

Continued measurements over the course of the next few centuries solidified the measurement of the speed of light, but it wasn't until the mid-1800s when things really started to come together. That's when the physicist James Clerk Maxwell accidentally invented light.

Maxwell had been playing around with the then-poorly-understood phenomena of electricity and magnetism when he discovered a single unified picture that could explain all the disparate observations. Laying the groundwork for what we now understand to be the electromagnetic force , in those equations he discovered that changing electric fields can create magnetic fields, and vice versa. This allows waves of electricity to create waves of magnetism, which go on to make waves of electricity and back and forth and back and forth, leapfrogging over each other, capable of traveling through space.

And when he went to calculate the speed of these so-called electromagnetic waves, Maxwell got the same number that scientists had been measuring as the speed of light for centuries. Ergo, light is made of electromagnetic waves and it travels at that speed, because that is exactly how quickly waves of electricity and magnetism travel through space.

And this was all well and good until Einstein came along a few decades later and realized that the speed of light had nothing to do with light at all. With his special theory of relativity , Einstein realized the true connection between time and space, a unified fabric known as space-time. But as we all know, space is very different than time. A meter or a foot is very different than a second or a year. They appear to be two completely different things.

So how could they possibly be on the same footing?

There needed to be some sort of glue, some connection that allowed us to translate between movement in space and movement in time. In other words, we need to know how much one meter of space, for example, is worth in time. What's the exchange rate? Einstein found that there was a single constant, a certain speed, that could tell us how much space was equivalent to how much time, and vice versa.

Einstein's theories didn't say what that number was, but then he applied special relativity to the old equations of Maxwell and found that this conversion rate is exactly the speed of light.

Of course, this conversion rate, this fundamental constant that unifies space and time, doesn't know what an electromagnetic wave is, and it doesn't even really care. It's just some number, but it turns out that Maxwell had already calculated this number and discovered it without even knowing it. That's because all massless particles are able to travel at this speed, and since light is massless, it can travel at that speed. And so, the speed of light became an important cornerstone of modern physics.

But still, why that number, with that value, and not some other random number? Why did nature pick that one and no other? What's going on?

Related: The genius of Albert Einstein: his life, theories and impact on science

Making it meaningless

Well, the number doesn't really matter. It has units after all: meters per second. And in physics any number that has units attached to it can have any old value it wants, because it means you have to define what the units are. For example, in order to express the speed of light in meters per second, first you need to decide what the heck a meter is and what the heck a second is. And so the definition of the speed of light is tied up with the definitions of length and time.

In physics, we're more concerned with constants that have no units or dimensions — in other words, constants that appear in our physical theories that are just plain numbers. These appear much more fundamental, because they don't depend on any other definition. Another way of saying it is that, if we were to meet some alien civilization , we would have no way of understanding their measurement of the speed of light, but when it comes to dimensionless constants, we can all agree. They're just numbers.

One such number is known as the fine structure constant, which is a combination of the speed of light, Planck's constant , and something known as the permittivity of free space. Its value is approximately 0.007. 0.007 what? Just 0.007. Like I said, it's just a number.

So on one hand, the speed of light can be whatever it wants to be, because it has units and we need to define the units. But on the other hand, the speed of light can't be anything other than exactly what it is, because if you were to change the speed of light, you would change the fine structure constant. But our universe has chosen the fine structure constant to be approximately 0.007, and nothing else. That is simply the universe we live in, and we get no choice about it at all. And since this is fixed and universal, the speed of light has to be exactly what it is.

So why is the fine structure constant exactly the number that it is, and not something else? Good question. We don't know.

Learn more by listening to the episode "Why is the speed of light the way it is?" on the Ask A Spaceman podcast, available on iTunes and on the Web at http://www.askaspaceman.com. Thanks to Robert H, Michael E., @DesRon94, Evan W., Harry A., @twdixon, Hein P., Colin E., and Lothian53 for the questions that led to this piece! Ask your own question on Twitter using #AskASpaceman or by following Paul @PaulMattSutter and facebook.com/PaulMattSutter.

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: [email protected].

Paul M. Sutter is an astrophysicist at SUNY Stony Brook and the Flatiron Institute in New York City. Paul received his PhD in Physics from the University of Illinois at Urbana-Champaign in 2011, and spent three years at the Paris Institute of Astrophysics, followed by a research fellowship in Trieste, Italy, His research focuses on many diverse topics, from the emptiest regions of the universe to the earliest moments of the Big Bang to the hunt for the first stars. As an "Agent to the Stars," Paul has passionately engaged the public in science outreach for several years. He is the host of the popular "Ask a Spaceman!" podcast, author of "Your Place in the Universe" and "How to Die in Space" and he frequently appears on TV — including on The Weather Channel, for which he serves as Official Space Specialist.

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• voidpotentialenergy This is just my opinion but i think L speed is it's speed because the particle part of it is the fastest it can interact with the quanta distance in quantum fluctuation. Light is particle and wave so the wave happens in the void between quanta. Gravity probably travels in that void and why gravity seems instant. Reply
• rod The space.com article wraps up the discussion with, "So on one hand, the speed of light can be whatever it wants to be, because it has units and we need to define the units. But on the other hand, the speed of light can't be anything other than exactly what it is, because if you were to change the speed of light, you would change the fine structure constant. But our universe has chosen the fine structure constant to be approximately 0.007, and nothing else. That is simply the universe we live in, and we get no choice about it at all. And since this is fixed and universal, the speed of light has to be exactly what it is. So why is the fine structure constant exactly the number that it is, and not something else? Good question. We don't know." It seems that the *universe* made this decision, *But our universe has chosen the fine structure constant to be...* I did not know that the universe was capable of making decisions concerning constants used in physics. E=mc^2 is a serious constant. Look at nuclear weapons development, explosive yields, and stellar evolution burn rates for p-p chain and CNO fusion rates. The report indicates why alpha (fine structure constant) is what it is and c is what it is, *We don't know*. Reply

Admin said: We all know and love the speed of light, but why does it have the value that it does? Why isn't it some other number? And why did it become such a cornerstone of physics? Why is the speed of light the way it is? : Read more

rod said: The space.com article wraps up the discussion with, "So on one hand, the speed of light can be whatever it wants to be, because it has units and we need to define the units. But on the other hand, the speed of light can't be anything other than exactly what it is, because if you were to change the speed of light, you would change the fine structure constant. But our universe has chosen the fine structure constant to be approximately 0.007, and nothing else. That is simply the universe we live in, and we get no choice about it at all. And since this is fixed and universal, the speed of light has to be exactly what it is. So why is the fine structure constant exactly the number that it is, and not something else? Good question. We don't know." It seems that the *universe* made this decision, *But our universe has chosen the fine structure constant to be...* I did not know that the universe was capable of making decisions concerning constants used in physics. E=mc^2 is a serious constant. Look at nuclear weapons development, explosive yields, and stellar evolution burn rates for p-p chain and CNO fusion rates. The report indicates why alpha (fine structure constant) is what it is and c is what it is, *We don't know*.

• rod FYI. When someone says *the universe has chosen*, I am reminded of these five lessons from a 1982 Fed. court trial. The essential characteristics of science are: It is guided by natural law; It has to be explanatory by reference to natural law; It is testable against the empirical world; Its conclusions are tentative, i.e., are not necessarily the final word; and It is falsifiable. Five important points about science. Reply
• Gary If the universe is expanding , how can the speed of light be constant ( miles per second , if each mile is getting longer ) ? Can light's velocity be constant while the universe expands ? So, with the expansion of the universe , doesn't the speed of light need to increase in order to stay at a constant velocity in miles per second ? Or, do the miles in the universe remain the same length as the universe 'adds' miles to its diameter ? Are the miles lengthening or are they simply being added / compounded ? Reply
• Gary Lets say we're in outer space and we shoot a laser through a block of glass. What causes the speed of the laser light to return to the speed it held prior to entering the block of glass ? Is there some medium in the vacuum of space that governs the speed of light ? Do the atoms in the glass push it back up to its original speed. If so, why don't those same atoms constantly push the light while it travels through the block of glass ? Reply

Gary said: Lets say we're in outer space and we shoot a laser through a block of glass. What causes the speed of the laser light to return to the speed it held prior to entering the block of glass ? Is there some medium in the vacuum of space that governs the speed of light ? Do the atoms in the glass push it back up to its original speed. If so, why don't those same atoms constantly push the light while it travels through the block of glass ?

Gary said: If the universe is expanding , how can the speed of light be constant ( miles per second , if each mile is getting longer ) ? Can light's velocity be constant while the universe expands ? So, with the expansion of the universe , doesn't the speed of light need to increase in order to stay at a constant velocity in miles per second ? Or, do the miles in the universe remain the same length as the universe 'adds' miles to its diameter ? Are the miles lengthening or are they simply being added / compounded ?

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