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1

Your logical error: you are confusing the direction of time and the direction of entropy. Elementary physical processes may be time-reversible. Complex processes are (nearly!) never reversible, due to the second law of thermodynamics. So your game should be about elementary processes. Also (simplified) models may be time reversible in your game, for ...


1

In a physics sense, the acceleration would still be downward (time is squared in acceleration, so reversing time doesn't make the square negative), but it's the second law of thermodynamics that's really being reversed. Instead of getting nudged off of a table, falling to the ground, and bouncing succesively smaller bounces, a ball would be shot from the ...


4

Imagine a flowerpot sitting on a ledge. A breeze blows the pot off of the ledge, and it falls to the ground. When it hits the ground it shatters into a bunch of pieces, it kicks up dust, it makes a sound, it vibrates the ground, and the shards come to rest. The time-reversal of this is that some pieces of flowerpot are sitting on the ground. Suddenly a ...


12

One of the problems you will encounter is causality. Imagine you have a ball resting on the ground. Without already knowing how it behaved in the past you cannot uniquely define the next frame of your game. You cannot tell if the ball should: move upwards vertically. move upwards in any direction. roll on the ground towards any direction. do nothing. ...


15

There is no mistake. The laws of physics themselves are reversible in time, but the solutions not necessarily so. Thus, the "behavior" of the universe itself does not show symmetry under time reversal, primarily due to the second law of thermodynamics. The second law is about the behavior of the solutions, is not a fundamental law in itself. In your specific ...


2

In Reverse Time, objects would experience a inversion of velocities and accelerations. Instead of a falling ball moving toward the ground and gaining velocity, it would be moving away from the floor and losing velocity. When it returned to the spot it was dropped, its velocity should equal 0. To achieve this, change the sign on it's velocity along the ...


2

Proporties that are independent of time will not change when time is reversed, forwards or backwards, or changed in any other way. Anything dependent of time will run backwards. In general we may say that any change of any proporty (causing a difference $\delta f(t)$ over a time difference $\delta t$ between "before" $t_{1}$ and "now" $t_{2}$, that is ...


4

To make such a game and have it make sense, you would have to use a much simpler physical system than anything you would reasonably encounter on Earth's atmosphere. For heat-dissipating systems, the laws of thermodynamics give time a direction: the direction of increasing entropy. Thus an object that falls to earth dissipates its energy, mostly as heat. You ...


34

The direction of the gravitational force would not change under time reversal. Your object would feel a force downward, just as it does usually. It might be easier to imagine you had a movie of an object under the influence of gravity. Drop the ball from rest some distance above the floor. You'll see it move downward and speed up. You'd interpret this as a ...


2

In reverse time, it would seem gravity is still attractive. But the quick impulse force that stopped the motion of something falling would instead send it upward at some inital velocity, which gets slowed by gravity. Otherwise, the object would accelerate from rest away from earth. My hunch would be that all conservative force fields remain the same ...


1

We know that different parallel universes- if they truly exist - are governed by different sets of laws. No we don't. If parallel universes exist, we know nothing about them. They could have the same laws, different laws, or no laws. in different direction the flow of time in our universe - ? The only thing that really defines the "direction" of time in ...



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