Do you think anything can travel faster than a photon?

Started by Baruch, February 05, 2017, 02:29:00 PM

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Baruch

Quote from: trdsf on February 26, 2017, 06:11:29 PM
I often feel much the same way about string theory.  I was only just starting to get my brain wrapped around QM, and boom, everything changed.  :)

This happened around 1900, with the new atomic facts ... electron, X-ray, radioactivity, the proof of atoms, the atomic nucleus and relativity theory.  That and Marconi's radio telegraphy.  Exciting times.  But based on actual experimental data.  String theory has no experimental data, not already explained by Quantum Field Theory.  It is not the fault of QFT that theoreticians are still unhappy with it.
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.

Cavebear

I expect that "things" will snap back to reality one of these days.  We were all twisted up (literally) about earth-centric planetary epicycles until they finally made no possible sense and WOW, someone changed our perspective to heliocentric and things made sense again.  It is obvious now, but it wasn't then.  Until it was.

We are overdue for a change in perspective.

Someday (I hope soon, but you never know), dark matter and dark energy will make sense, spacetime will be resolved in a 3d Universe, and we will all say "oh well, of course, how obvious", etc.
Atheist born, atheist bred.  And when I die, atheist dead!

trdsf

Quote from: Cavebear on March 02, 2017, 09:36:12 AM
Someday (I hope soon, but you never know), dark matter and dark energy will make sense, spacetime will be resolved in a 3d Universe, and we will all say "oh well, of course, how obvious", etc.
That's kind of the thing about the real game changers in science: in retrospect, they often look obvious.  Which is why it takes a real genius to spot them.
"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

Cavebear

Quote from: trdsf on March 02, 2017, 11:30:07 AM
That's kind of the thing about the real game changers in science: in retrospect, they often look obvious.  Which is why it takes a real genius to spot them.

And I hope for a real game-changer soon.  Things are getting too unreal and it is time for a revolution to reality.
Atheist born, atheist bred.  And when I die, atheist dead!

fencerider

dont get to frustrated cavebear. The idea that nothing can travel faster than light is still a ridiculous and unproven hypothesis. It matters not that it was proposed by the likes of Einstein. well.... we are a long time away from even coming close to the speed of light. It's a moot point in our lifetime.

There is also the idea that if you move at the speed of light then time slows down for you. Sorry but if time slows down then you are not moving at the speed of light. There is a serious flaw in the equation somewhere. The most likely way to find the missing piece is to solve the equation for when you are moving at the speed of light and time is a constant.
"Do you believe in god?", is not a proper English sentence. Unless you believe that, "Do you believe in apple?", is a proper English sentence.

Baruch

Quote from: fencerider on April 11, 2017, 01:03:10 AM
dont get to frustrated cavebear. The idea that nothing can travel faster than light is still a ridiculous and unproven hypothesis. It matters not that it was proposed by the likes of Einstein. well.... we are a long time away from even coming close to the speed of light. It's a moot point in our lifetime.

There is also the idea that if you move at the speed of light then time slows down for you. Sorry but if time slows down then you are not moving at the speed of light. There is a serious flaw in the equation somewhere. The most likely way to find the missing piece is to solve the equation for when you are moving at the speed of light and time is a constant.

Platonists never believe that reality changes, depending on your POV.  Or in this case, physical measurement of the same event by different observers.
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.

SGOS

Traveling at high speeds is so 1950s.  It became obsolete with artificial worm holes.  No waiting for a shuttle to the space station, no drinking cup after cup of coffee while waiting for the next departure, and no need for all the magazines to read on the way to another galaxy.  I refuse to go by space ship anymore, even when I can find a direct flight with no stops.  In my business at my salary, my time is too valuable.  And the food they serve these days is an insult.  They are hardly ever on time, and getting bumped because the flight is overbooked just wastes my time.  I don't even consider it.  I only travel by star gate.  For local travel between cities, I use Amtrak.

Baruch

Quote from: SGOS on April 11, 2017, 08:35:57 AM
Traveling at high speeds is so 1950s.  It became obsolete with artificial worm holes.  No waiting for a shuttle to the space station, no drinking cup after cup of coffee while waiting for the next departure, and no need for all the magazines to read on the way to another galaxy.  I refuse to go by space ship anymore, even when I can find a direct flight with no stops.  In my business at my salary, my time is too valuable.  And the food they serve these days is an insult.  They are hardly ever on time, and getting bumped because the flight is overbooked just wastes my time.  I don't even consider it.  I only travel by star gate.  For local travel between cities, I use Amtrak.

When United runs space travel, it will really suck when the overbooked passengers are shoved into the air-lock ...
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: fencerider on April 11, 2017, 01:03:10 AM
dont get to frustrated cavebear. The idea that nothing can travel faster than light is still a ridiculous and unproven hypothesis. It matters not that it was proposed by the likes of Einstein. well.... we are a long time away from even coming close to the speed of light. It's a moot point in our lifetime.

There is also the idea that if you move at the speed of light then time slows down for you. Sorry but if time slows down then you are not moving at the speed of light. There is a serious flaw in the equation somewhere. The most likely way to find the missing piece is to solve the equation for when you are moving at the speed of light and time is a constant.
That's about as complete a misunderstanding of special and general relativity as you could ask for.

Time slows down for you as seen by an outside observer.  You traveling at 99.9% of the speed of light will not actually feel time slow down -- a second is still a second, a minute is still a minute, an hour is still an hour.  And you observing someone back on Earth will think their time has slowed down, because all motion frames are relative, and you can treat your moving away from them as equivalent to them moving away from you.  Furthermore, your time and their time do not have to synch up again.  Time is not absolute -- there is no such thing as a reference frame where it ticks away in measured, unvarying beats.  There are only an infinitude of overlapping relative frames of reference.

And this time dilation effect has practical, real-world uses.  The GPS in your phone or on your car's dashboard relies on it in a fundamental way.  If the competing effects of the relative speeding up of time due to the satellites' altitude and slowing down of time due to their velocity weren't taken into account, your position would be wrong by something on the order of eleven kilometers.  And not eleven kilometers total, but eleven kilometers error per day.

Einsteinian relativity is one of the most profoundly confirmed theories in physics, from the explanation of the precession of Mercury's orbit in 1915 to the confirmation of the existence of gravitational waves last year.  We're getting to be hard pressed to find places to break it, and it's starting to look like the only place we can is inside black holes.  And those are a little tricky to get on a lab table.
"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

Cavebear

Quote from: fencerider on April 11, 2017, 01:03:10 AM
dont get to frustrated cavebear. The idea that nothing can travel faster than light is still a ridiculous and unproven hypothesis. It matters not that it was proposed by the likes of Einstein. well.... we are a long time away from even coming close to the speed of light. It's a moot point in our lifetime.

There is also the idea that if you move at the speed of light then time slows down for you. Sorry but if time slows down then you are not moving at the speed of light. There is a serious flaw in the equation somewhere. The most likely way to find the missing piece is to solve the equation for when you are moving at the speed of light and time is a constant.

Reality tells me that time is constant and moving.  I like your thoughts!
Atheist born, atheist bred.  And when I die, atheist dead!

SGOS

Of all the cockamamie theories and observations like QM and Relativity, the thing that is easiest to wrap my head around is that time is not the constant that the ticking pendulum of a grandfather clock suggests.  If time didn't exist before the bang, why should we think it is some kind of constant?  It's apparently much too wispy in nature to be continually existent, let alone constant.

I can even see the relationship between speed of light and time, and how moving at the speed of light affects our perception of the time we leave behind.  It makes perfect sense, but it's still weird, suggesting there is an even more fundamental relationship between light and time, almost as if light and time are the same thing, but that we have evolved to perceive that single property of the universe from two wholly different perspectives.

Does that make sense to anyone besides me?

Maybe this is a poor analogy, but I'll try.  I hope it doesn't wreck what I'm trying to say.  What is an elephant?  Is it a thing we see or a thing we hear?  The perception of hearing is wholly different from the perception of seeing, as if we are experiencing two different things, but it's not two different things.  It's just one thing perceived in two different ways.  It's easy to grasp this, because it's something we know, and know well as second nature.  But what of things that we don't know as well, could similar conclusions be reached?

Would there be a single property "light/time," just as when we talk about "space/time?"  "Light/space/time" perhaps?  They all seem related to me.  Maybe they are not, but they seem to work together in unison, although often in inverse relationships.  As light slows down, time speeds up, as space stretches out, time slows down.  It reminds me of the law of conservation of mass and energy.  One expands at the expense of the other.

Baruch

"almost as if light and time are the same thing" ... they are.  I can explain if you want.

"It reminds me of the law of conservation of mass and energy." ... that relationship is directly related to the space/time relationship.  Mass is like space, time is like energy.
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.

SGOS

Quote from: Baruch on April 12, 2017, 01:02:24 PM
"almost as if light and time are the same thing" ... they are.  I can explain if you want.
I just looked this up.  I don't understand it very well, so I assume I wouldn't understand your explanation either.  I get the impression that the explanations are metaphysical and about as speculative as my own speculations; They are sort of thought provoking hooey.  I found this one response to the question interesting, if not all that informative.

QuoteLight and time are not related, because the "speed of light" is just an accidental property of light. It is not really anything to do with light in particular, it is a geometrical quantity that tells you how to change units of space and time. â€" Ron Maimon Aug 31 '11 at 3:10

This site needs a special category for quasi-mystical, physics-struggles-with-metaphysics, category questions! BK, the simple fact is nobody has a clue about the absolutely biggest questions. But it's worth learning the "conventional" state of the art thinking; which (extremely generously) people here are happy to (repetitively) explain when "big question" questions arise. Enjoy! Why not read one of the many, many really outstanding popular mysteries-of-time-and-space books which are available today?  â€" Fattie Jul 22 '14 at 10:34

Baruch

Sorry, I can do physics too.  But not like a teenage Mongolian girl contortionist.  This isn't metaphysics ...

https://www.youtube.com/watch?v=lpBL4SovbxA
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.

Baruch

Actual physics ...

1. A thing can be assigned a value, in some cases negative, or zero, or positive or some combination.  For instance the distance between my home and work (about 5 miles).

2. When the context has more than one dimension however, in addition to a value, you also have another concept, that of direction.  Work is 2 miles W and 3 miles S from home.

3. A thing with a value but no direction is called a scalar.  It is one dimensional.

4. A thing with both a value and a direction is called a vector.  It is two or more dimensions.

5. When I drive from home to work, it takes about 15 minutes.  It isn't instantaneous.

6. We can take the ration of the distance to the amount of time it takes ... which works out to 20 miles per hour.  This is called my speed.

7. The vector describing my travel has a length, which is equal to the speed.  But it also has a direction.  The velocity of a thing and the speed of a thing are related, but not the same.

8. The geometry of my trip has two axes, that run zero to a positive number on each axis, according to the scale I am using (assuming the same scale for both directions).

9.  I can make a 3-d graph, with the horizontal axes being the spaces and the vertical axis the time.  I can make the vertical axis start at zero, and based on some scale for time, have it increase positively as I go up the graph.  Now my trip is a line in 3-d, but one axis isn't the same type as the other two.  The space dimensions (conventionally taken at 90 degrees to each other, and angle measured positively from the X axis to the Y axis as I rotate about the vertical time axis looking down (right handed convention)) are related, they can be changed into each other or some combination by a change of frame of reference.  Similarly I can rescale the time axis at will or the two space axes together at will (independently of the time rescaling).

10. Turns out that in extreme circumstances, the description in #9 is incorrect, it only works at low relative speed, but not at very high relative speed.  This is because physics isn't something we construct independently of observation.  A mathematician can get away with anything, so long as he is consistent.

So good so far.  Turns out (and I will explain later why) it is necessary to change the relationship between that time axis and those two conjoined space axes, in order for the math to match the actual measurements.  Einstein realized that there was a problem with this thought experiment, and that there was another, equally internally consistent model, which matched actual measurements better.  He realized this while watching the tram, the clock tower and his cup of coffee .. while having lunch with his young friends while working at the Patent Office.

Sneak preview:

https://www.youtube.com/watch?v=6569GBcQKTs
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.