E8 Theory That Unifies Quantum with Relativity... Maybe

Started by SGOS, September 10, 2019, 02:13:45 PM

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SGOS

Quote from: Unbeliever on September 11, 2019, 01:33:51 PM
I've been wondering lately how time and gravity are related. Time slows down in a reference frame that's in a strong gravity field, and I wonder whether it's the slowing of time that's important in the "tug" of gravity. Maybe things "want" to move as slowly through time as possible, so they "gravitate" in the direction of slower time.
These concepts are interesting.  More to bend your brain, and it doesn't seem unreasonable.  One day maybe, this will open new doors and send us in a new direction.

Unbeliever

Quote from: Baruch on September 11, 2019, 04:51:47 PM
And some claim time is secondary, not primary.  But if that is so, so is space (SR ties them together).  My POV.  Everything is moving at the speed of light (not velocity of light).  Speed is the length of the 4-vector in space-time.  And of course each particle vector isn't at the same point in space-time.  So basically N test particles at N points.  The 4-vectors don't point in the same direction.  They are never co-located.  But the length is always the same.  This is where people's grasp of Relativity goes bad ... "regular matter can't accelerate to the speed of light" ... "light is always at the speed of light".  Not quite true.  Matter particles can point in different directions from each other, but never point in the same direction in 4-d as any light particle.  Light particles can point in different directions from each other, but never in the same direction in 4-d as a matter particle.  Different propagation magisteria.  It doesn't describe how they locally interact.  QFT does.

So no question of tachyons, warp drives etc.  Right now you and I are both moving at Warp One, but not in the same direction, not from the same event (4-d location).

Time flow.  Light and matter both flow at the same speed, in a vacuum.  When light and matter interact (index of refraction) is is a classical approximation that the speed of light in the material is slower than it was in the vacuum.  But this is an approximation.  That isn't what is happening in QFT.  In QFT there are no test particles, no trajectories.  Just statistical experiment outcomes.  It doesn't even describe reality in the absence of humans.


According to Lewis Carrol Epstein, in his book Relativity Visualized, we all travel at the speed of light, since everything travels at a space-time velocity of exactly "one." Faster travel through space means a slower passage through time, and vice versa, but the combination of the two always equals one.
God Not Found
"There is a sucker born-again every minute." - C. Spellman

Cavebear

Quote from: Baruch on September 11, 2019, 04:51:47 PM
Everything is moving at the speed of light (not velocity of light). 

Almost nothing moves at lightspeed...
Atheist born, atheist bred.  And when I die, atheist dead!

Baruch

Quote from: Cavebear on September 11, 2019, 06:09:08 PM
Almost nothing moves at lightspeed...

Typical ignorance ... speed not equal to velocity.  Unless you mean ... no perfect vacuum ... that that is only experimental light speed.  All particles are themselves in vacuum ... relative to that they only move at light speed.

See, Star Trek and most of sci-fi are based on lay ignorance of SR.  Sorry, no free lunch, no Space Communism etc.
Ha’át’íísh baa naniná?
Azee’ Å,a’ish nanídį́į́h?
Táadoo ánít’iní.
What are you doing?
Are you taking any medications?
Don't do that.

trdsf

Quote from: Unbeliever on September 11, 2019, 01:33:51 PM
I've been wondering lately how time and gravity are related. Time slows down in a reference frame that's in a strong gravity field, and I wonder whether it's the slowing of time that's important in the "tug" of gravity. Maybe things "want" to move as slowly through time as possible, so they "gravitate" in the direction of slower time.
I don't think they're related as such; it's just that gravity bends space and since the speed of light in a vacuum is a constant, if the distance is changed then the time also must change so that c isn't changed.

Quote from: Unbeliever on September 11, 2019, 01:33:51 PM
It's been said that acceleration and gravity are equivalent, but there is a difference. In a gravity field, such as the surface of the Earth, time flows more slowly at sea level than it does at, say, 40 miles higher. But if you were accelerating in a space ship that was 40 miles long, you wouldn't measure any difference in the flow of time between the front end and the back end. Any time dilation would be the same no matter where in the ship you were.
A 40 mile long ship is accelerating as a unit, so you're going to make the same measurements both fore and aft.  With a globe like the earth as the source of the acceleration force, you can move away from the center of mass, so that a sufficiently exact time measurement taken at sea level will not match a measurement taken the same way at 40 miles above sea level.  The reason an accelerating ship is used as a model for some gravitational field effects is because acceleration and gravitational field strength are measured in the same terms: meters per second squared.
"My faith in the Constitution is whole, it is complete, it is total, and I am not going to sit here and be an idle spectator to the diminution, the subversion, the destruction of the Constitution." -- Barbara Jordan

Unbeliever

Quote from: trdsf on September 11, 2019, 11:53:13 PM
I don't think they're related as such; it's just that gravity bends space and since the speed of light in a vacuum is a constant, if the distance is changed then the time also must change so that c isn't changed.

But what does it mean to "bend" space? From our perspective, it seems to mean compression and expansion, but time is also affected, by slowing or speeding up. This gravitational time dilation is, I think, part and parcel of the bending of space/time. I just wonder is it the cause or the effect? Or is it more of an epiphenomenon that means little?
God Not Found
"There is a sucker born-again every minute." - C. Spellman

Baruch

#36
Quote from: Unbeliever on September 12, 2019, 01:24:10 PM
But what does it mean to "bend" space? From our perspective, it seems to mean compression and expansion, but time is also affected, by slowing or speeding up. This gravitational time dilation is, I think, part and parcel of the bending of space/time. I just wonder is it the cause or the effect? Or is it more of an epiphenomenon that means little?

Not quite.  Light doesn't speed up/slow down relative to vacuum.  The path gets shorter or longer.  Consider a bow.  The arch of the bow goes from point to point, same as the taut string.  The length along the bow is longer, and it is thus curved.  This isn't strange relative to SR.  In SR, measured lengths vary depending on conditions.  To keep the speed of light constant, the measured duration has to vary inversely.

Now what is real once you have SR and GR?  The idea that measurement isn't objective across all circumstances ... was a reason for older scientists to reject relativity theory.  In a given circumstance ... measurement is consistent.  In that way, objectivity is maintained, in a narrower sense.  This is because the older model, absolute space and absolute time ... objectivity would be there for all circumstances.  As it turns out, only the speed of light maintains that larger consistency.

Einstein's view is that this isn't an epiphenomenon.  What you measure, is what is.  It isn't a distortion of some Platonic reality.  So Einstein is an empiricist and rationalist.  Plato was only pre-rationalist (and fantasist) because proper logic didn't get invented until Aristotle and the Stoics came along later.  But what is real with QT or QFT ... there isn't any agreement yet on that.  Except that all accurate models, predict the same experimental results (the Interpretation Problem).  From Bohr's POV, that is what is real.  What the experiment looks like, before you measure, isn't real.  Even Einstein couldn't accept that.  But Einstein was wrong.  This is the "Measurement Problem".  There are still many Quantum scientists who don't like it.  The new Entanglement Experiment didn't solve this, it was already part of the (all accurate models).
Ha’át’íísh baa naniná?
Azee’ Å,a’ish nanídį́į́h?
Táadoo ánít’iní.
What are you doing?
Are you taking any medications?
Don't do that.

trdsf

Quote from: Unbeliever on September 12, 2019, 01:24:10 PM
But what does it mean to "bend" space? From our perspective, it seems to mean compression and expansion, but time is also affected, by slowing or speeding up. This gravitational time dilation is, I think, part and parcel of the bending of space/time. I just wonder is it the cause or the effect? Or is it more of an epiphenomenon that means little?
That's why they call it spacetime -- they're linked, like electricity and magnetism are linked.  When space is curved by gravity, time is also altered by gravity.  Neither is properly speaking the cause of, or the effect of, the other.  Matter tells space how to bend, and space tells matter (and light) how to move; there's no way to divorce the two, nor give primacy to one over the other.

Curved or not, from the viewpoint of the light, it still looks like it's moving in a straight line.  It's like being in an airplane carefully following the line of latitude at 40° -- from your perspective aboard the plane, you have clearly not deviated from a straight line, but (fuel concerns notwithstanding) if you keep following it you eventually discover yourself back where you started, so you have clearly followed a curved path that never looked curved.
"My faith in the Constitution is whole, it is complete, it is total, and I am not going to sit here and be an idle spectator to the diminution, the subversion, the destruction of the Constitution." -- Barbara Jordan

Sal1981

I'm interested in the physics that involves bending space, through other means than gravity. Particularly the Albecurrie Warp drive, given GR equation of warp fields. Just means we'll have to get our hands on some quite exotic matter and energy generation.

PBS Space Time had a vid on it 4 years ago.

https://www.youtube.com/watch?v=94ed4v_T6YM

Unbeliever

That drive takes some sort of exotic matter that doesn't exist, like unobtainium.

But the question of out-of-the-box spaceship drives has not been entirely neglected by scientists:

https://www.scientificamerican.com/article/the-good-kind-of-crazy-the-quest-for-exotic-propulsion/

One possibility being looked at is something called the Mach effect:

https://www.nasa.gov/directorates/spacetech/niac/2018_Phase_I_Phase_II/Mach_Effect_for_In_Space_Propulsion_Interstellar_Mission/
God Not Found
"There is a sucker born-again every minute." - C. Spellman

Baruch

Freelunchium is as rare as Unobtanium.

Exotic matter is dangerous, remember a new Star Trek movie about that ...
Ha’át’íísh baa naniná?
Azee’ Å,a’ish nanídį́į́h?
Táadoo ánít’iní.
What are you doing?
Are you taking any medications?
Don't do that.

Unbeliever

Survival is dangerous, so danger is life's middle name. We drop from our mothers' wombs, crawl across open country under fire, then fall into our graves.
God Not Found
"There is a sucker born-again every minute." - C. Spellman

Baruch

Quote from: Unbeliever on September 14, 2019, 01:42:16 PM
Survival is dangerous, so danger is life's middle name. We drop from our mothers' wombs, crawl across open country under fire, then fall into our graves.

You will never achieve SJW-hood with that bad attitude ;-)
Ha’át’íísh baa naniná?
Azee’ Å,a’ish nanídį́į́h?
Táadoo ánít’iní.
What are you doing?
Are you taking any medications?
Don't do that.

trdsf

Quote from: Unbeliever on September 14, 2019, 01:35:10 PM
That drive takes some sort of exotic matter that doesn't exist, like unobtainium.

But the question of out-of-the-box spaceship drives has not been entirely neglected by scientists:

https://www.scientificamerican.com/article/the-good-kind-of-crazy-the-quest-for-exotic-propulsion/

One possibility being looked at is something called the Mach effect:

https://www.nasa.gov/directorates/spacetech/niac/2018_Phase_I_Phase_II/Mach_Effect_for_In_Space_Propulsion_Interstellar_Mission/

Unfortunately, that first link is behind a paywall.  Can you give a nickel tour of it?
"My faith in the Constitution is whole, it is complete, it is total, and I am not going to sit here and be an idle spectator to the diminution, the subversion, the destruction of the Constitution." -- Barbara Jordan

Unbeliever

God Not Found
"There is a sucker born-again every minute." - C. Spellman