A photon does have infinite speed from a certain point of view. That would be its own view. Since ZERO time elapses no matter the distance it covers you could say that is infinite speed. However since the distance it travels in the direction it is headed is only two dimensional it has covered no distance at all....So speed is just the wrong scale to consider here - you need to consider energy or momentum.
This isn’t a trick - it’s always the case that you can turn infinite scales into finite scales and vice versa. The math behind it is called “conformal transformation.” The physicist Roger Penrose has a way of drawing a picture of the entire infinite universe on a finite piece of paper. It’s called a Penrose diagram,...So you can think of “speed” as a conformal transformation of an energy/momentum scale. Speed is like the “on diagram” distance in a Penrose diagram - it “runs out” within the finite page. And speed “runs out” at c.
- There's proper velocity, which is a measure of how far the light moves for every second that passes for it.
- There's time dilation, which is a measure of how much the light advances into the future for every second that passes for it.
- There's rapidity, which is analogous to an angle; but it's an angle between space and time.
The only measure that's finite is classic velocity, the ratio of proper velocity to time dilation.
is the time-like separation between two events (points in spacetime identified by when and where they are). In the same way that the collection of all points in space with the same forms a circle, the collection of all events in spacetime with the same
forms a hyperbola.
This notion of proper time is an important one in Relativity, because it's an invariant quantity: no matter what frame of reference you use (in effect, the choice of valid coordinate systems), the separation between two events
will always be the same. This is similar to how the distance between two points is always the same no matter how much you spin around...The equation for proper time is . That use of a minus instead of a plus is what makes all the difference, as that changes it from an equation of a circle to the equation of a hyperbola. (The in the equation is a spacetime conversion factor, saying in effect that there are 299,792,458 meters in a second.)...Any finite amount of “rotation” will fall short of a true diagonal, because the change in will always be slightly less than the change in ; and infinite “rotation” will exactly reach that diagonal, where ....the ratio between them approaches a finite limit. That ratio is what we traditionally call speed: a change in distance () over a change in time ().Photons (and anything traveling at “c”) do not have a reference frame *at all*. This is a consequence of the definition of the invariant speed and of a rest reference frame. It is fairly simple.
- Anything that travels at the invariant speed “c” travels at that speed in ALL reference frames.
- A rest reference frame is one in which the object is at rest (traveling with 0 velocity) relative to itself.
- If an object travels at the invariant speed “c” then in must travel at that speed in ALL reference frames, including its own rest reference frame.
the concept of time for an object traveling at light speed becomes meaningless. This is because, according to relativity, as an object's velocity approaches the speed of light, time dilation increases without bound. At light speed, the equations that describe time dilation lead to undefined results, indicating that the passage of time cannot be defined for such an object.
Light has mass in the sense that it contains a quantity of energy, but it is not referred to as mass when it travels freely at c. If that energy is absorbed by matter, it then shows up as additional mass. Whenever energy is bound up in things that collectively travel at less than c, all of that energy becomes classed as mass, but if you break the object up and turn it entirely into electromagnetic radiation that shoots off in multiple directions at c, none of that energy is called mass.
You’ never see ‘your’ time slow down. ‘You’ always see things as if ‘you’ are at rest. Other things are always moving relative to (stationary) ‘you’....I meant from the POV of an observer, who was overseeing both events simultaneously. They'd see light in both frames (of reference) travel at c, and the events in each frame would be observed to pass more slowly than if observing a,stationary frame.
yes this is very much how “you” is defined as an “external observation.” Louis de Broglie’s Law of Phase Harmony was a critique of relativity from the perspective of quantum physics. de Broglie called the Law of Phase Harmony his “greatest discovery” and he has a Nobel Prize yet his “Law of Phase Harmony” is not taught in physics classes! Why? Well Bell’s Inequality that got the Nobel Prize and disproved Einstein is still misunderstood by other Nobel Prize physicists as Professor Jean Bricmont has detailed so well. Quantum physics professor Basil J. Hiley who had collaborated with David Bohm, who confirmed the Law of Phase Harmony, tried to explain to Nobel physicist Roger Penrose that indeed it is noncommutativity as nonlocality that is the secret of the foundation of reality in quantum biology. I have a paper on this secret - it’s based on listening as logical inference - NOT an external visual observation as the definition of the I or Self. see the academic journal “Cosmos and History” - peer-reviewed, open access Dec. 2024 issue for “noncommutativity music as biophysics” article. You can also read Nobel physicist Gerard ’t Hooft’s article “Light is Heavy” for a good start.
If two objects in inertial frames are moving in relation to one another and yet both measure light as traveling at the same speed, that means that the relative movement of one MUST be causing distortions in space and time (the components of speed) in the frame of the other. At the speed of light, those distortions are so great that space is contracted to 0 and time dilated to infinity. Something moving at the speed of light carries the most possible distortion it can create in the observer's frame while still having a meaningful existence.
light is just one example of something that moves at this speed, and the reason it does is because it has no mass. Gravity also moves at the same speed. Anything with no mass must move at the special speed in the eyes of any observer.
AI:
Noncommutativity can violate invariancebecause it introduces a dependence on the order of operations, which breaks symmetries like Lorentz invariance in physical theories. In many standard theories, the order of operations does not matter, meaning the result is the same regardless of the sequence (this is the commutative property). However, in a noncommutative theory, this is not true, leading to consequences like the violation of fundamental symmetries, such as the conservation of energy-momentum, which is linked to translational invariance
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you (and your reference frame and clock) are always moving at the speed of light through spacetime, and what you think of as stationary is really moving in the time only direction....so that now, *relative* to the former stationary state, you are moving thru space too. But you’re moving less thru time, your clock runs slower *relative* to a clock left in the frame we called stationary,
Galileo illustrated the relativity of motion by noting that the motion of a boat drifting down a placid river was undetectable below decks in the boat.
https://www.quora.com/Can-you-explain-simply-why-time-slows-as-you-move-faster
proper time may imply a different amount of time measured along some space-time path — which is one of the deepest answers to the so-called twin paradox — but it says nothing about the rate of passage, as it is called.
More importantly, Pythagoras’s theorem is different in space-time. In normal space, we can say and it then follows that the shortest distance between two points is a straight line. In space-time, the equivalent equation (using only one spatial dimension for simplicity) isand the minus sign has serious counter-intuitive consequences, such as a straight path between two points actually maximising the proper time (i.e. the time as would be experienced, or measured, on such a path).
What this means is that any irregular (non-straight) path for one twin — whether it is a simple turnaround or a series of random accelerations and decelerations — will mean that the proper time for that path will be less than the one for something travelling at a steady constant velocity (i.e. a straight world-line in space-time). The other explanations are simply special cases of this. ...
The age discrepancy arises from the different space-time paths that they take. When they meet at some given space-time location then they will see the difference.
If two people simply walked different paths to get to a common meeting point, they could compare their routes and one might notice that they had used more shoe leather. This is similar only insomuch as they become aware when they meet, and not before. Neither has experienced time at a faster or slower rate — merely a different amount of it........
The complication is because the rotating twin’s constantly changing inertial frame can be said to have a speed relative to the other twin. I suspect that the ageing difference would be visible to them — good question!...........
if you count ticks of clocks, one at rest and the other three moving fast in three perpendicular directions (as seen by the stationary clock), together with one for each pair as above, and square those counts, you obtain uniquely a quadratic form. It’s then an experimental fact that this quadratic form counts the squares of clock ticks on all clocks. In particular it makes no difference which clocks to use to measure it.
And it’s nondegenerate. So the orthogonal complement of the clock is three dimensional. It’s also an experimental fact that on the orthogonal complement this quadratic form is negative definite, so it’s minus a Pythagorean metric, and that this Euclidean space is in fact “space”, as experienced by that clock.
That’s the essential physical content.
If you understand this much, the rest is working out the mathematical consequences of the model.
In spacetime, two observers in different reference frames can no longer agree on “now.” Neither can they agree on “when.” “Now” for one observer might be the past for the other. Clocks do not tick at the same rate in spacetime. The distance from one place to another and the time it takes to get there is malleable. Straight lines are no longer straight and gravity is a pseudo-force caused by curvature in the presence of matter. There may be places in the universe where the passage of time no longer has any meaning and the known laws of physics break down.
But don’t get too comfortable with spacetime. Like all models, it has limits. Some of the math used in Einstein’s theory break down under extreme conditions like black holes or at the big bang. Solving that conundrum and unifying Relativity with Quantum Mechanics is the next holy grail of physics.
https://www.quora.com/What-is-spacetime-8
Relativity says that there is a universal “now”, but it is impossible for me to verify the conditions of now at another place without getting a signal from there or to travel there. But both of them takes time and by the time I get that information, time will pass and things change by the time I verify them. I see the sun the way it was 8 minutes ago not the way it is now.
Physical processes happen all over the universe at a certain rate. There is such a thing as psychological experience of time and it is the result of remembering how things used to be and seeing the difference between that and how they are now. “My room was organized and now it’s messy” gives me the sensation of time passing.
But to have a quantitative sensation of time we need time measuring devices with an accurate rate. That can be moon cycles, seasons, sun dials, hour glasses and clocks.
Spacetime is a concept of imagining a tiny clock at every single point in space that measures the local time at that particular point. But this is just a model because obviously there is no clock at every single point in space.
Special relativity’s idealized spacetime model says that without mass all these clock are and remain synchronized all the time. This is not true because there is gravity everywhere and the clocks do get out of synch. But general relativity deals with that.
“Time curvature” affects the rate of clocks. As a general rule, in a gravitational field, clocks tick slower than elsewhere. This effect is primarily responsible for gravity. All other effects, including space curvature, contribute only a tiny, tiny correction except in the presence of extremely strong gravitational fields (surface of a neutron star, immediate vicinity of a black hole.)
https://www.quora.com/What-is-space-curvature-as-opposed-to-time-curvature-really
- : for something moving at the vacuum speed of light, spatial curvature and time curvature contribute equally, doubling the effect of gravity on their trajectories.
To wit: Time curvature affects clocks; space curvature changes geometry.
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