/sci/ - Science & Math

>>12697694
Time is just a measurement.

Either things happen or don't.

>>12697694
Time is not subjective. It is objective. When you travel at some speed, your objective time measurement dilates. The spacetime interval s^2 = r^2 - t^2 is invariant among frames. This gives us an objective way to track events within spacetime that all observers must agree on. What we lose, however, is the notion of simultaneity, which only requires events to occur at the same time regardless of spatial separation. Simultaneity is now relative, but not subjective.

>>12697748
Is this why the universe is said to be expanding? And why a star that died millions of years ago is still visible from earth? Also, what are r and t in that interval if s is speed?

>>12697694
>Newton says position and motion are relative
heh b-based
>Einstein just extends this and plagiarizes some geometry shit no one cares about
NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO

>>12697748
If simultaneity is the variable, to what degree is it manipulable? Can the moment a rabbit runs a meter vary greatly from location to location, or are the scales to small to observe this phenomenon?
If the size of an event increases as its objective speed rises, is the big bang the absolute limit of this phenomenon seeing as we are living within it, or can the expansion be infinite?

>>12697842
It doesn't explain why the universe is expanding. Nobody really knows "why". All we know is it's expanding and we use the big bang model to explain how.

Yes this is why if a star explodes billions of years ago, we can see it exploding today. It's really rather wild. It's the same principle that lets us do particle physics. Construct a cosmic ray detector to measure muons coming in from the atmosphere. Theyre short lived and should decay far before they ever reach our detector. And that's true. However they're moving so quickly that time stretches for them, and hence to them they decay rather rapidly whereas to us, we can measure them traveling for times longer than their lifetime.

s is not speed. It's a scalar space-time displacement that gives an objective "location" in spacetime between two events. r is displacement in physical space whereas t is time.

http://www.drphysics.com/syllabus/interval/interval.html

>>12697873
>>12697873
I wouldn't call simultaneity a variable. It's merely something we have intuition about that's no longer valid in relativity. The speed scales at which this occur are orders of magnitude faster than the fastest object humans have ever made. The factor by which time dilates is [math]\gamma = 1/\sqrt{1-\beta^2} [/math] where [math] /beta [/math] is your speed as a fraction of the speed of light. Theoretically, humans are about to launch a rocket that will, at its fastest speed while sling shotting around the sun, be about 400,000 mph. The speed of light is about 700,000,000 mph. This yields a time dilation factor of about 1.0000002.

The absolute limit is the speed of light, where the spacetime interval is formally zero everywhere. This means photons will experience the birth and death of the universe simultaneously. Remember, simultaneity is relative in accordance with speed. The sign of the spacetime interval determines whether the distance between two objects is time-like (part of observable universe) or space-like (causally disconnected regions of spacetime).
>https://physics.stackexchange.com/questions/10756/difference-between-timelike-and-spacelike-vectors

Laughing all these retards posting their thinking about the subject, not realising they are false.

Think about this: Lorentz transformation is just a 1-1 transformation. It is unneeded bloat tranformation and everything can be described classical way.

>>12698574
Lorentz transformation is only possible on the Minkowski metric or generalizations of it. It's invalid on a Euclidean metric.

>>12698667
Look at this parrot talking nonsense. Who need gaygowski metric? Nobody.

You Will Never Be a Wormhole

>>12697883
Are we certain the universe is expanding though? I thought Einstein say the universe is finite and unbounded, and the observable red shift that was used to say the universe is expanding could also be used to explain how its finite but unbounded.

>>12697694
you cant, your brain fools you , you dont know how the universe really looks like or feels like, your no more than an ant

>>12698574
Then how can you account for other perspectives, it may be 1-1 within yourself but youre squeezed or expanded to others

>>12701256
That becouse I AM SQUEEZED/EXPANDED.

Do not think with transformations. Physicists small brains cannot understand this mathematical theory.