Recent content by guptasuneet

Thanks everyone for participating in the discussion and for some mind opening replies. What I have understood from the discussion till now is: Spacetime is definable independent of the presence of any particles in it Concept of time cannot be defined for a particle with zero rest mass...

Does a photon traveling at c experience time? A muon generated in the upper atmosphere (from cosmic rays) and traveling at 0.995c experiences time contraction of ~10 times, i.e. it travels the 15 km distance to Earth in 5 microseconds internal time, as compared to 50 microseconds external time...

An accelerating frame might have objects in constant spatial coordinates relative to each other (within its frame of reference). However, All objects in any such uniformly accelerating frame shall feel a constant force and proper acceleration. Therefore it is not an inertial frame. In Special...

I understand that. Let me try and think of some of the implications of an 'Absolute Velocity' universe (if I can).

It was just a thought process on why the universe is the way it is. Similar to why we have 3 physically observable dimensions, or why we have 4 observed forces? But then the answer is perhaps the anthropogenic principle.

I am not claiming that our universe has any absolute velocity. That's been experimentally confirmed and validated. I am just thinking theoretically here. Just like we can conceive of 1 and 2 dimensional universes or even multi-dimensional universes, is it possible to conceive of a universe with...

In our relativistic universe, there is no method to determine velocity of self without an external reference, which implies that there cannot be any absolute velocity. However, as you correctly point out absolute acceleration is the reading derived from an accelerometer attached to the object...

There are several theoretical analyses of 2 dimensional or of multi-dimensional universes. Now, we live in a special universe that follows Newton's first law (A body at rest or a body in motion shall continue to be at rest or in motion till acted upon by an external force), and consequently...

An accelerating frame is not in rest with reference even to itself. So how can we compare forces or relativistic effects between two co-moving but accelerating frames.

While the events will be distributed at distinct points in the 4-dimensional spacetime, for the massless photons, all interactions should still apparently happen instantaneously.

Exactly, if the land dweller exits the ship, come to an immediate stop and jumps back in after some time (immediately going up to the ship's velocity), then the clocks on the spaceship will be ahead of the watch on his hand, because time moved faster for him, relative to the frame of reference...

Thanks, I'll lookup on the radiation dominated universe. I know theoretically that space and time evolve from space-time geometry. However, I am not able to give to myself a practical interpretation without mass/energy. It is like the chicken and egg problem. Which came first, space-time or...

Yes, but in the end the space traveler lands back on land and returns to the reference frame of land (or he lands on some distant planet which is in the same reference plane as the land from which he started). Therefore, the apparent time contraction is seen by the land dweller happening for the...

I agree. There can be no rest frame of a photon, because a photon has no rest mass and always travels at c. Similarly, there cannot be a rest frame of any other object that also has zero rest mass. My question is that in a theoretical universe composed only of massless objects (i.e. with zero...

I understand the difference between traveling in a spaceship and staying on land, and why time contracts for the spaceship traveller and not for the land dweller. All of relativity (distance compression, time contraction, etc.) is explained at relativistic velocities and never at c. However...