Friday, June 29, 2007

Why we can't travel in time.

It just occurred to me why time travel may not be possible. That is because time isn't necessarily a dimension.

The main reason people think of time as a dimension is because physics models use time as a dimension just like space, and it works well.

However, just because you can model time as a dimension, doesn't mean that it is a dimension. I can model an image on a flash disk using *.jpg format. However, the binary conforming to the jpg format isn't an image at all. In the same way, time doesn't have to be a dimension, and the past and future don't necessarily exist.

By the way, really the same may be true of the other 3 dimensions as well.



jocko said...

Congrats for joining blogspot. We are also blogspoter (Tamar, a.k.a., Beth, my daughter has probably already provided the URLs).

FWIW, your comment on time is similar to the thought of some philophers - notably Augustine who considered the past to be memory and the future to be anticipation.

However, I believe your theory does not account for a number of objective observations, e.g., subatomic particles in cloud chambers, decay of radioactive elements, cosmic background radiation and other observations.

Fish Goldstein said...

1. Nice to meet you in cyberspace.

2. I'm not sure what is meant by Augustine's "memory" and "anticipation". Do you know what he is talking about? I think the thrust of what I was saying wasn't so much what time definitely is but what is isn't definitely.

3. I don't think modern QED, as expressed in Feynman's book, QED, supports the 4D matrix at all. What observations are you thinking of?

4. Thanks for your comment, I appreciate having a way to refine the ideas.

jocko said...

Augustine's dead so we don't know what he meant for sure but clearly he thought time was way different from space.

I don't have Feynman's book but he has a lot of diagrams with particles moving right to left (time negative). I'll grant you that he probably was a 3+1 guy ("yeah there are 4 dimensions but that time thing is not like the others").

Fish Goldstein said...

Take a look at the QED/Feynman diagram articles on Wiki. QED is a fine book. I think one of the most beautiful elements of the book is the scientific level. Meaning, that he admits that we don't understand the why or how of what is going on. We only understand what happens.

The problem with the framework, is the difficulty in understanding how causality plays into the equation. QED suggests that causality is independent of time, as long as the speed of light isn't infinity.

jocko said...

I noticed I can get a used version of the book for less than $5 on Amazon. Maybe on your recommendation I'll get the book.

Yes, our intuitive understanding of causality is a victim of QED. However, causality also falls by the side of the road in other sciences where math is well developed; even in good old Newtonian physics. Remember F=MA . Causality is in the equation only if you assume a force from the outside or if you assume a mass and accel from the outside.