Bonus points for physics test

Well obviously it breaks most laws of physics, conservation of energy, thermodynamics, quantum mecahnics. Probably most of the others. Though it is a fun philosophical  idea i'll grant you.

I still don't see how it breaks the law of conservation of energy.

Quote from: bowler on February 21, 2010, 11:01:26 AM

Well obviously it breaks most laws of physics, conservation of energy, thermodynamics, quantum mecahnics. Probably most of the others. Though it is a fun philosophical  idea i'll grant you.

I still don't see how it breaks the law of conservation of energy.

Well many of the stochastic laws that the idea assumes to be completely deterministic assume conservation of energy. I'm not trying to crush it as I appreciate it is a cute philosophical thought.

H + H > He + energy

He + energy > H + H?

H + H > He + energy

He + energy > H + H?

milk + flour + egg -> pancake

pancake -> milk + flour + egg?

Alas this is so rarely the case. It would make medicine so much easier.

bullet + person .....

milk + flour + egg -> pancake

pancake -> milk + flour + egg?

This would work if you could put the energy of deformation back into the proteins and such. Which would be perfectly viable if the process of cooking was initiated backwards in time.

Quote from: bowler on February 21, 2010, 01:04:53 PM

milk + flour + egg -> pancake

pancake -> milk + flour + egg?

This would work if you could put the energy of deformation back into the proteins and such. Which would be perfectly viable if the process of cooking was initiated backwards in time.

Protein folding is a highly complex process, if you reverse a thermal process you almost certainly never get the same shape back. Thats one of the many reasons living things don't react well to large deviations from their nominal temperature. If I drop a glass on the floor then it will smash. Its very unlikly that anything I do to the shards of glass will yield the original glass. Even melting down will give a subtly different glass.

Protein folding is a highly complex process, if you reverse a thermal process you almost certainly never get the same shape back. Thats one of the many reasons living things don't react well to large deviations from their nominal temperature. If I drop a glass on the floor then it will smash. Its very unlikly that anything I do to the shards of glass will yield the original glass. Even melting down will give a subtly different glass.

That's because all of those actions are initiated from a point in time at which the glass is broken. If the glass were intact in the future, and somebody initated an action backwards in time to break it, then it would be broken now. The effect, from our perspective, would be reassembly of the pieces.

Quote from: bowler on February 21, 2010, 02:16:28 PM

Protein folding is a highly complex process, if you reverse a thermal process you almost certainly never get the same shape back. Thats one of the many reasons living things don't react well to large deviations from their nominal temperature. If I drop a glass on the floor then it will smash. Its very unlikly that anything I do to the shards of glass will yield the original glass. Even melting down will give a subtly different glass.

That's because all of those actions are initiated from a point in time at which the glass is broken. If the glass were intact in the future, and somebody initated an action backwards in time to break it, then it would be broken now. The effect, from our perspective, would be reassembly of the pieces.

I appreciate that. I simply showing how incompatible it is with physics as we understand it now. You can't 'flip' the time arrow and expect to get the same stuff happening in reverse.

I appreciate that. I simply showing how incompatible it is with physics as we understand it now. You can't 'flip' the time arrow and expect to get the same stuff happening in reverse.

I have yet to come across a single equation or law in physics which requires time to move in a particular direction.

Quote from: bowler on February 22, 2010, 01:02:05 AM

I appreciate that. I simply showing how incompatible it is with physics as we understand it now. You can't 'flip' the time arrow and expect to get the same stuff happening in reverse.

I have yet to come across a single equation or law in physics which requires time to move in a particular direction.

As far as i'm aware only thermodynamics requires the 'arrow' of time. That still doesn't mean that if we were to flip the arrow of time now it would be like rewinding a tape. I mean a train can go backwards or forwards along a railway line, though going backwards is no guarantee that you will see the same people again. Go back to you ligh going back to the star to reverse the fusion process. If the light is now going backwards all its scatters off of matter are purely stochastic. Just because it bounced of a molecule at 60 degrees the first time does not guarantee that if time were reversed it would bounce off at -60 degrees.

As far as i'm aware only thermodynamics requires the 'arrow' of time. That still doesn't mean that if we were to flip the arrow of time now it would be like rewinding a tape. I mean a train can go backwards or forwards along a railway line, though going backwards is no guarantee that you will see the same people again. Go back to you ligh going back to the star to reverse the fusion process. If the light is now going backwards all its scatters off of matter are purely stochastic. Just because it bounced of a molecule at 60 degrees the first time does not guarantee that if time were reversed it would bounce off at -60 degrees.

My idea necessitates a deterministic universe in which light is neither going backwards nor forwards, but it is doing both. In other words, everything has two origins, one in the past and one in the future, and because the universe is deterministic each one is in perfect balance with the other.

My physics teacher told me that I get 10 bonus points on our next test if I do something impossible. That impossible thing is providing an example of a situation (and the necessary equations to prove it) in which the total entropy of the universe decreases. His example was freezing water: he showed that when you freeze water the entropy in the sample decreases, but increases in the surrounding environment more than it decreased in the sample, thus resulting in an overall increase in entropy.

There has to be some way to decrease entropy, even if it doesn't actually work in practice, it doesn't matter, as long as I can show it to work mathematically. People of FES who know what they are doing, UNITE! Help me get bonus points.

What rules did he give you as far as what defines "universe" and do you have to follow rules of physics?

Give him a Carnot Heat Engine (or any heat engine for that matter) with the "cold sink" as a parallel universe (or really any source outside "the system").  The universe would no longer be an isolated system, but again I don't know what rules he gave you.

Quote from: bowler on February 22, 2010, 01:02:05 AM

I appreciate that. I simply showing how incompatible it is with physics as we understand it now. You can't 'flip' the time arrow and expect to get the same stuff happening in reverse.

I have yet to come across a single equation or law in physics which requires time to move in a particular direction.

A particle of mass m is in a one dimensional box of length L. Suddenly, at t = 0, we measure its coordinate to be some particular value q (0 < q < L).

• What is the probability for finding the particle in the ground state at times t > 0?
• What is the probability that the particle was in the ground state at times t < 0?

Quote from: bowler on February 22, 2010, 01:02:05 AM

I appreciate that. I simply showing how incompatible it is with physics as we understand it now. You can't 'flip' the time arrow and expect to get the same stuff happening in reverse.

I have yet to come across a single equation or law in physics which requires time to move in a particular direction.

i'm not 100% sure, but i think the CP violation of kaons could be such a case.   

Quote from: Parsifal on February 22, 2010, 01:19:10 AM

Quote from: bowler on February 22, 2010, 01:02:05 AM

I appreciate that. I simply showing how incompatible it is with physics as we understand it now. You can't 'flip' the time arrow and expect to get the same stuff happening in reverse.

I have yet to come across a single equation or law in physics which requires time to move in a particular direction.

i'm not 100% sure, but i think the CP violation of kaons could be such a case.   

Thats another very specific exacmple.