Is there anything faster than light?

I was curious if there's anything faster than light, or would we ever be able to travel between galaxies do you think? What kind of energy would it require and technology?

 

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Entities called "tachyons", which always travel faster than light, have been hypothetically proposed. More about them here: https://en.wikipedia.org/wiki/Tachyon

As you can see, it seems to be a dead end, so far. As for intergalactic travel, not at superluminal speeds.The best way might be to move a whole world, slowly, over millions of years. Of course the beings that arrived in the destination galaxy might by then have become rather different from those that left the original one!

 

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As someone has proposed: light!

 

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Space time expansion is not restricted by the otherwise universal speed limit.

 

Explain

 

Sure! The most distant galaxies are receding at >"c" evidenced by their cosmological redshifts.
http://scienceline.org/2007/07/ask-romero-speedoflight/
The universal speed limit of 'c"applies to massive objects only.

 

Two galaxies, far enough separated as to not be gravitationally bound to each other, experience cosmological redshift which is proportional to distance. Indeed, the space between them is growing at a rate proportional to the distance between the galaxies. This is called Hubble expansion. Therefore at large enough distances, the total distance between the two will be growing faster than the speed of light.

This violates no laws because the galaxies aren't speeding through space -- indeed, they may each be at zero velocity relative to the locally-perceived CMBR and local average matter density -- so locally they are at rest but cosmological expansion causes the empty space to give them effective large velocities when measured in non-local coordinates.

 

Oddly phrased. The above two statements are not related.

1] The universal speed limit of c applies just as much to massless objects as to massive objects.

2] Galaxies receding at > c is a result of the fact that objects cannot exceed c when measured locally.

 

Agreed, I did put it rather too simplistic....
http://www.askamathematician.com/20...iverse-expand-faster-than-the-speed-of-light/
First, the universe doesn’t expand at a particular speed, it expands at a speed per distance. Right now it’s about 70 kilometers per second per megaparsec. That means that galaxies that are about 1 megaparsec (1 parsec = 3 lightyears and change) away are presently getting farther away at the rate of 70 km every second, on average. Galaxies that are 2 megaparsecs away are presently getting father away at the rate of 140 km every second, on average.

and this.......
http://www.preposterousuniverse.com...never-expands-faster-than-the-speed-of-light/
. Experts get this one wrong all the time. “Inflation was a period of superluminal expansion” is repeated, for example, in these texts by by Tai-Peng Cheng, by Joel Primack, and by Lawrence Krauss, all of whom should certainly know better.
1.The expansion of the universe doesn’t have a “speed.”

During inflation (as well as today, since dark energy has taken over), the scale factor, which characterizes the relative distance between comoving points in space, is increasing faster and faster, rather than increasing but at a gradually diminishing rate. As a result, if you looked at one particular galaxy over time, its apparent recession velocity would be increasing.

 

This sounds like a process that, even if possible, would be unobservable.

 

Is this really news to you? You did not realize that the recession velocity of a distant galaxy can exceed c?

 

Relative to what, exactly?

This:

https://en.wikipedia.org/wiki/Recessional_velocity

has no claim to be an exception either to Special Relativity nor to the following discussion.

Take a good hard look at the sky including cosmologically distant galaxies. If there weren't spiral galaxies that had a familiar shape like ours, over any stretch of time we could measure, those stars would appear, for all intents and purposes, to remain in "fixed" relative positions. Only their Doppler shifts give us any clue that they are moving relative to us. What exactly would a Doppler shift look like for something receding from us FTL? That's right; shifted all the way into the red until it became unobservable.

Science doesn't deal exclusively with that which can be observed, but in this case, perhaps we should be making an exception. Why? Because there is no observable evidence that anything matter or energy can ever exceed the speed of light. If it did, there would be Cherenkov radiation, wouldn't there? Do we actually see any?

Things which are quantum entangled are the only things in this universe that can respond FTL, and that process does not involve any bulk transfer of matter or energy that is FTL

 

Us. The observers.

 

Worth mentioning that galaxies more distant than the horizon can exist, there's nothing stopping them, but we can't see them from here. In fact they have to exist; if the horizon were actually the edge of the universe it would cause effects that we would be able to see. As a result, though the most distant galaxies we can see (13 billion light years or so) must have moved since they emitted the light until they're now about 40 billion light years away, we know that there have to be more galaxies out about 25% further than that, so we place the boundary of the knowable universe at 50 billion light years and say that we know that the universe therefore has to be at least a hundred billion light years across.

So the short answer is, yeah, they can exist, in fact we know they do, but we can't see them. So, snicker, things can go faster than the speed of light, you just can't see them.

 

well, the emissions could become microwaves. or longer.

 

Absolutely. Odd that danshaven assumes we cannot see beyond the red end of the visible spectrum of light.

In fact, the sky is far and away more informative at radio wavelengths than it is in the vanishingly narrow band of visible light. That's why radio astronomy is huge.

 

I grow weary of responding to posts like this one, so this will be the last time.

Okay, lets talk about "us, the observers".

You, "the observer", are composed of bound energy. The energy E=mc^2 that makes you up is bound into particles (or standing waves of rotationally propagating energy, if you prefer) and those particles comprise basic atomic structure bound by strong nuclear, electroweak, and EM forces that physics has gone to rather a lot of bother to understand in all of its glorious quantum detail.

If all of that E=mc^2 bound energy (matter) were combined with an equal amount of E=mc^2 bound energy that happened to be antimatter, then 100% of the bound and unbound energy of both matter and antimatter would be quickly converted into as many photons (unbound energy) along with an explosion comparable to a small supernova. If you instead wished to remain in your present atomic configuration and instead expend all of the E=mc^2 energy in the entire rest of the universe in order to propel yourself at a speed exceeding that of light relative to your present state of motion or at rest, that still would not be a sufficient amount of energy in order to accomplish the task. In actual fact, no amount of added kinetic energy would suffice.

Those photons produced by the matter-antimatter explosion all would all travel at the speed of light relative to all observers in any inertial reference frame. How do you propose to make them move faster than light (FTL) relative to anything else, eh? Gonna push 'em, that's all. Won't work. Don't you remember the Special Relativity thought experiment about the flashlight on the front end of a relativistic locomotive? You can Doppler shift the light, but no matter how fast the train goes, you can't make the beam of photons travel any faster than the speed of light. You can Doppler shift them to well beyond the energies of gamma rays if you wish, but they still travel at the speed of light. Relative to ANYTHING and EVERYTHING else, BECAUSE THE SPEED OF LIGHT IS INVARIANT. Quantum entanglement is the sole exception to the rule, and it really isn't an exception either, because when entangled states change, nothing matter or energy physically propagates.

How about the train itself? Made of matter too, isn't it? Unless you make something out of tachyons (or else "inflatons"), then nothing else made of matter and energy can travel faster than light. For the bound energy that is matter bound in atomic structure, this rule is now even harder, because the Higgs mechanism is made manifest by a particle we just discovered which itself has mass, to the tune of 125 GeV. Since it has inertial mass itself as well as imparting it to all electrons, quarks, electroweak bosons, neutrinos and their respective antiparticles, it won't be exceeding the speed of light any time soon either, will it? The 2% of E=mc^2 atomic structure Higgs imparts inertia to is important enough that without it, atomic structure itself can literally not exist. Gluons and color charge won't cut it, even if it is 98% of E=mc^2 atomic structure.

In the case of both tachyons and inflatons, the difference is the mixure of GROUND UNICORN HORNS, PIXIE DUST, EXOTIC MATTER, and perhaps a pinch of Huckleberry Finn added for good measure. Since none of these are made of matter or energy, it makes perfect sense that they would be able to break a law of physics as solid as Special Relativity, doesn't it? Or perhaps you've simply been watching too much Star Trek or other Gene Roddenberry fare. Can't blame you for that, but you should probably understand, this isn't science, right? Or maybe you simply choose not to believe in that particular law of physics. I would recommend you not try this kind of thought experiment for real with the law of gravity next, or not without a parachute, a baloon, an aircraft, or a at least a helmet to support and protect the mostly empty space between your ears.

There's no shame here, or at least, none I seem to be able to effectively tap into. Apparently, a preponderant number of highly compensated and credentialed scientific professionals, even some high profile ones like Alan Guth harbor the same sort of poorly thought out ideas about the ease of breaking out of the confines of hard limits on what matter and energy can do imposed by Special Relativity. Good luck with that, and G-dspeed. In the present universe comprised only of energy transfer events, you have totally missed the train. Maybe you can catch up to the rest of them riding an inflaton or a unicorn or something. Last time I checked, the Higgs boson had been discovered, but the inflaton or even the graviton had not. Perhaps in 50 more years or so, I could be proven to be wrong.

And that is more physics in one explanation than a post like "us, the observer", or even someone like Alan Guth ever deserved.

 

You grow weary of direct, succinct answers to simple straightforward questions?

"Relative to what?"
"Us. The observers."

What follows seems to be a huge amount of rhetoric. Can you highlight the part where it is relevant to the thread?

Is it possible that your entire argument boils down to 'nothing can travel faster than c'? And that is what you are using to refute recessional velocity > c?

 

Permanent ignore status it is then.

Thank you for going to all the trouble of reading the first two sentences of my response. I hope you will apply yourself in similar fashion to all of your science studies. If it does not pain you too much.

Please give my warmest regards to paddoboy.