Faster than Speed of Light? Yes.

[ballaratdragons]

OK, the debate has rattled on long enough without any real answers: Is anything faster than the speed of light?

I say yes, simply by using common sense.

I'm sure you have all heard of a 'Black Hole'.

The best known attribute of a Black Hole is that it does not allow light to escape.
How can it do this?

By simple reasoning I realise that the Black Hole is 'sucking in' faster than light can escape, meaning that the sucking is faster than the Speed of Light.

Sounds correct to me :)

So, whatever the action of the inwards motion into a Black Hole is called, it is faster than the Speed of Light. :thumbsup:

End of Lecture.
I'll take my Nobel Prize now thanks :P

[redbeard]

Sounds Good :cool2:, wonder if anyone is going to smash that theory :atom:?

[ballaratdragons]

I hope not, because I am be submitting a paper on it :thumbsup:

[ballaratdragons]

The only theory I am up against is the one that states that to a distant observer, clocks near a black hole appear to tick more slowly than those further away from the black hole.

Due to this effect, known as 'Gravitational Time Dilation', an object falling into a black hole appears to slow down as it approaches the event horizon, taking an infinite time to reach it. At the same time, all processes on this object slow down causing emitted light to appear redder and dimmer, an effect known as 'Gravitational Redshift'.
Eventually, at a point just before it reaches the event horizon, the falling object becomes so dim that it can no longer be seen.
But I am studying this theory in more detail to see if it is accurate.

It has already been stated by many Physicists that light cannot 'fade' nor 'end'. However, it can be redirected (Gravitational lensing), or absorbed (by hitting an object).

[mswhin63]

Hi Ken,

I tend to disagree although Black Holes are still essentially unknown. I would prefer to side with scientist at this stage although it is still theory.
I always thought similar to you as there is mass in the black hole and impossibly that mass is supposedly infinte (which is hard to believe). In saying that light would escape but it would have a lot of trouble. Considering our own sun light takes approx 500,000 years to escape the centre of the sun it could be feasible that it could take light billions of years to escape a black hole and the universe as it stand has not existed that long enough to see that reaction.

It is all conjecture and as i have learn't it is nice to have theories but to have a definitive answer like "Yes" is really not science.

On another note Black Holes eject jets out from it core so to speak although this is theorised as coming from the event horizon. It is not impossible to suggest that some of the light that we can't see is converted to jet energy.

I have not learn't enough to be totally sure though and arguements are welcome.

[Dave2042]

Interesting take on it, and good luck.

By the way, on your specific point, I think the 'standard' reason for light's inability to escape a black hole is that the distortion of space-time is so great that spatial dimensions acquire a time-like character. That is, space gets 'tilted over' in the same direction as time. Now a fundamental aspect of time is that nothing can avoid progressing in it - unlike space, you can't stand still in it. So inside a black hole, space has that property too - everything is 'dragged along' through space to the singularity in exactly the same way it is dragged along through time outside the black hole.

That said, here is a link to a paper from a bunch of people claiming to be overturning the whole concept of space-time on which the 'standard' rests. I am extremely skeptical, but can't claim enough expertise to say they're definitely wrong.

http://phys.org/news/2012-04-physicists-abolish-fourth-dimension-space.html

Hope this is of use or interest.
Also by the way, to what extent have you studied standard GR? I can't get a sense of this from your post.

[alistairsam]

Ken,

Why would the absence of light from a black hole mean light travels faster into it? a simplistic understanding of black holes is that its gravity is so great that light cannot escape, how is this related to the speed of light?

eg, a funnel with a vacuum pump behind it. if that is sucking in smoke in a room, it would appear the smoke travels faster toward the funnel. but that's because the smoke was travelling slow to start with.
if the same smoke was travelling at a rate faster than what the pump can extract, it would still disappear into the funnel without any change in speed??
its entry speed would depend on the rate at which the pump can extract air.
do we know these qualities in a black hole?

I'm not sure if Einsteins theories accounted for black holes, I'm guessing it did in which case it would have been factored in before the assertion that nothing can travel faster than light?

[GeoffW1]

Hi,

Mmm, it must be my imagination, did I feel a gentle pull at my leg? :rofl:

Whatever, my understanding is that the vast gravity of a black hole distorts the very fabric of space and time around itself. It is not that space-time is static and unaltered there, and then gravity acts on light just by itself.

This distortion has the result that light, which would normally be travelling in more or less a straight line, and at or nearly the speed of light (of course ;)), cannot escape because the very path of the light through the fabric of space is warped, bent back and redirected inside the event horizon.

If you could ride a photon, you would not perceive it being any different at all (but what a ride :eyepop:) .

Cheers

[cwjohn]

Hi

Alistair is correct in that there is no relationship between the Swartzchild radius and the speed of any particle at that radius just as there is no relationship between a body entering or leaving the earth and the Earth's escape velocity.

Photons will of course travel at the speed of light towards a black hole but their orbits will depend on their approach angle and the angular momentum of the object in question (whether it is rotating). Massive particles will be affected in a similar fashion but their speeds will vary depending on their gravitational mass and and the aforementioned factors. As the particle approaches the speed of light any information pertaining to the particle will be redshifted out of existance in our frame of reference. Of course in the frame of reference of the particle it will be destroyed due to the effects of gravity.

To the best of my knowledge the only known possibility for ftl are theorised particles that are to this point a mathematical abstraction and the non localised effects of entanglement which in simple terms has thus far been explained by consideration of the different frames of reference of the entangled particles, which do not allow a meaningful transfer of data. I suspect either candidate has some way to play out as yet and dependent on reasonable experimental data which may be some time coming.

[ballaratdragons]

No Alistair, I didn't say light travels any faster. You are off on the wrong direction.

What I am saying is that if light is not able to escape, something else (suction? gravity?) must be going slightly faster to prevent the light from travelling outwards against it. :thumbsup:

[ballaratdragons]

Geoff, shhhh, nothing wrong with sparking some good brain exercises, and a bit of thought-provoking conversation ;)

I am enjoying the discussion :)

[alistairsam]

Ken,
even if that's the case, we know that the effects of gravity are responsible, forces involved don't consist of particles and therefore are not travelling themselves. They would influence photons or wavefronts, but force doesn't "travel" as there aren't any particles involved.
so not sure how you mean "something else" must be going ftl.

[alistairsam]

Ken, good to "spark" things once in a while ;)
time better spent than swearing at the darn clouds.

[Meru]

Though my opinion is oh so humble on these deep and meaningful thoughts, I just wanted to say that this thread is most enjoyable to read :D And my 2 cents, Malcolm makes a very reasonable thought of line. On the other hand, we're only limited by our current knowledge of the universe around us, so who's to say we're right - we're only right because we justify it to ourselves

Not sure if I contributed anything meaningful but it was worth a try :D

[cwjohn]

Light is not able to escape because spacetime is distorted to such an extent that it cannot. If one uses the rubber sheet analogy which I personally dislike we see the earth creating a small bump in spacetime and the sun creating a much greater one. As a result particles take a different trajectory to a straight line. In the case of a black hole the "bump" is in fact an infinite hole and at a certain point a photon simply "falls" down the hole and cannot escape to the outside. There is no suction as such.

On the issue of forces, these are generally understood now to behave as particles e.g gluons, photons, photons, bosons, and are subject to the the limitations of the speed of light.

[Barrykgerdes]

All this implies that these minute particles have mass and if they have mass they cannot reach the absolute speed of light. Therefore the measured speed of light is in error. This would explain why nutrinos appear to travel faster than the speed of light when in fact they do not even reach the "absolute speed of light"

Of course this is all theory manipulated to fit into a finite universe when the universe is infinite.

[cwjohn]

All incorrect statements.

Photons are massless and travel at the speed of light this statement in itself being oxymoronic as "light" is a stream of photons.

There is absolutely no evidence that neutrinos travel faster than light. There are a couple of disgraced senior physicists who will testify to this fact.

The observable universe being finite occurs as a result of observations and the application of special and general relativity, not the other way around. The actual universe may be finite or infinite. It does not matter and we may never know.

[CDKPhil]

My basic understanding of light, is it has no mass. So how does gravity affect something that has no mass?

If space time is distorted as it is with a sun. The light is effected indirectly by the mass of the suns effect on the fabric of space time and not gravity directly effecting the light itself.
So we would see a bending or distortion in the light, but the light would not be bent, it would be the bending or distortion of space time.

So a black hole distorts space time to an extent that the light that enters it would travel along until it until it came out the other side. How ever long that might take would depend on how much of a distortion was created in the fabric of space time.

Feel free to shoot me down in flames:lol:

Cheers
Phil

[Dave2042]

Can I make an over-arching point (which I think I've made elsewhere).

These days, a physical theory is simply:


a set of definitions of observable quantities; and
a set of equations relating the observable quantities to each other.

It is often useful to also have an interpretation of the theory to make it easier to handle for practical purposes. Examples are curved space-time in GR, or the wave-function collapse in QM (Copenhagen interpretation). However, the interpretation is not actually part of the theory, can be ignored or rejected, and can sometimes mislead.

On this basis, the question of what 'really' happens inside a black hole is actually meaningless. The equations predict what we see. If that matches observation, then good, if not, then we need another theory.

I agree it's fun to play around with these things, but I like to remember that at rock bottom it's just equations of observables, and any serious objections or alternatives to a theory really have to be expressed as equations of observables. (Which, being really hard, is why I try to stick to just having fun.)

[Miaplacidus]

Not related to black holes at all (or not much at least, I think), but...

I've always wanted to hear the sensible explanation for why, if I'm spinning around on my swivel chair (or standing on a rotating Earth, say), and all the galaxies are therefore appearing to whizz around me at speeds much faster than the speed of light, and with frames of reference supposedly being merely relative to one another and not in any way "privileged", how all the clever people get out of this conundrum by being able to insist that only I am the one accelerating and that the rest of the universe is not.

I'm not saying it's not true, mind. Just wondering is all...

[2stroke]

Time to spark up a bob marley hahaha, acid may be needed to ride that train of thought :)

Bill Hicks
Today a young man on acid realized that all matter is merely energy condensed to a slow vibration, that we are all one consciousness experiencing itself subjectively. There's no such thing as death, life is only a dream, and we're the imagination of ourselves.

Great theory ken, lol now i'am going to spend the next few days reading into black holes. I would put this on CN and see what the guys come up with :)

[stardust steve]

Great concept Ken. Just about sums it up and sounds right to me.:thumbsup:

[cwjohn]

Fascinating stuff.

Which galaxies precisely appear to be travelling at faster than the speed of light?

Which clever people insist that we are the only ones accellerating and the rest of the universe is not?

References would be fine. Pointers to papers on these matters would be better.

[avandonk]

If a photon had a mind it would perceive it's travel across the known Universe in an instant!

Unless of course you see it and then cruelly it remains with you as a sensation in your brain and never gets to the other end of the Universe! The same goes for your cameras etc.

Bert

[cwjohn]

Having a mind presupposes matter, thereby denying such a perception. Of course one can theorise that one can have mind without matter, this being a metaphysical question I guess.

[Regulus]

Chris you rubber sheet analogy (which I also dislike but can't think of a better one) made me think thusly.
If a sun has thrown off mass and then collapsed to a point and is now a black hole, why wasn't the original sun with it's greater mass also a black hole??
Is it to do with the smaller area the mass is concentrated into?

Dave2042 thanks for the article link it was interesting.

[bojan]

The explanation can be found in a book "Gravity from the bottom up", by Bernard Schutz (I think..).
It's about Mach principle..
I will post the related quote later today... when I find it.

[bojan]

My mistake, it was "The Fabric of the Cosmos - B. Greene".

This is very interesting book, you should read it...

Some relevant quotes are below:


So, space and time and moving in space and time are relative things, but spacetime is different, it is absolute.

[LAW]

Hawking Radiation. That is all.

[Dave2042]

Regulus

You have correctly answered your own question. To elaborate, the Schwarzchild radius (ignoring spinning and charged matter) is simply defined for any point mass, right down to fundamental particles (leaving aside the fact that at this point QM is well in play). A non-point mass (eg a star) is a black hole iff it is so dense that it is all inside its Schwarzchild radius.

Glad someone enjoyed that link.

[Colin_Fraser]

I got to thinking about this.
If light, lots of it, could escape a black hole, then the hole would not be black :shrug:

[Regulus]

Thanks David.
Thanks Bojan and for the book referral as well. Just looked it up on Amazon and found an ebook version.
Just reading Lisa Randall's new book Knocking On Heavens Door. I enjoyed her first one Warped Passages too.

[ballaratdragons]

Correct Colin :thumbsup:

[Colin_Fraser]

Had another thought (this hurts). Light may be able to escape a black hole.
If objects collapse to a point where they become black holes, and the gravity is great enough to suck in nearby objects, then these objects may have collapsed as well.
If that happens then perhaps there is no light in the black hole :confused2:

[Miaplacidus]

Thanks, Bojan. Much appreciated.

[GeoffW1]

Hi,

It's a bit lightweight, and has been on several times already, but Prof Brian Cox is doing his thing on SBS2 at 08.30pm tonight in "What Time is it?", looking at the Arrow of Time, and how we cope with it.

Cheers