The arrow of time

[Wade]

The arrow of time: Backward ran sentences… | The Economist

I'm not even going to pretend I understood this article except the gist of it that time does have a PREFERRED direction, note the capitalization. The article used this word in the subtitle which to me indicates that there is an alternative direction (unless I'm reading too much into it.)

 

[Randall]

The arrow of time: Backward ran sentences… | The Economist

I'm not even going to pretend I understood this article except the gist of it that time does have a PREFERRED direction, note the capitalization. The article used this word in the subtitle which to me indicates that there is an alternative direction (unless I'm reading too much into it.)

They always make this stuff sound more complex than it is. What they're saying is that time is dependent on the movement of particles in a particular direction ( duh ) and that because antimatter is supposedly a mirror image of normal matter, hypothetically for antimatter time would run in the opposite direction. Of course there are several problems with that interpretation of the nature of time. But that didn't stop them from getting a pile of cash to play with a particle accelerator.

 

[Wade]

That does clear it up for me thank you. reading it in your words leads me to think that there is nothing ground breaking in the findings as I was aware (in a matter of speaking) of how time is measured.

Would this finding imply (despite your mention of problems) if antimatter existed as a natural course of things in a massive quanity (say a galaxy) that time would move backwards, at least relative to our concept of it ?

Furthermore would that mean to any inhabitants of that galaxy that the movement of time as we know it would be a equally queer concept to them ? It almost sounds like anything made of antimatter would start "old" and grow younger

Now I'll really suck myself down a rabbit hole, would gravity also exist (or anti-gravity ) in this galaxy and be able to be harnassed to slow down the backwards progression of time ?

I think I see what you mean when you mention that there is problems with this definition/concept of time. I am reminded of an arthur c. clarke short story I read some years ago called Time's Arrow where a scientist created a negative entropy environment in a area also being worked by some paleontologists. It was a absolutely brilliant story, it would have made a great twilight zone episode. If any forum members are still with me on this post, I heartily recommend it.

 

[Randall]

That does clear it up for me thank you. reading it in your words leads me to think that there is nothing ground breaking in the findings as I was aware (in a matter of speaking) of how time is measured. Would this finding imply (despite your mention of problems) if antimatter existed as a natural course of things in a massive quanity (say a galaxy) that time would move backwards, at least relative to our concept of it ?

Furthermore would that mean to any inhabitants of that galaxy that the movement of time as we know it would be a equally queer concept to them ? It almost sounds like anything made of antimatter would start "old" and grow younger

Now I'll really suck myself down a rabbit hole, would gravity also exist (or anti-gravity ) in this galaxy and be able to be harnassed to slow down the backwards progression of time ?

I think I see what you mean when you mention that there is problems with this definition/concept of time. I am reminded of an arthur c. clarke short story I read some years ago called Time's Arrow where a scientist created a negative entropy environment in a area also being worked by some paleontologists. It was a absolutely brilliant story, it would have made a great twilight zone episode. If any forum members are still with me on this post, I heartily recommend it.

I don't claim to be an expert, but then again I just saw a National Geographic exposé on "experts" that indicated the "experts" were no better at predicting outcomes than dart throwing monkeys. Anyway, to clarify a bit more, it seems to me that their concept of time in this study is flawed. Simply because the particles themselves are a mirror image doesn't mean that time is. The reason is that time is dependent on change. Direction doesn't matter. To use a simple analogy, let's say one of these particles is your car, it wouldn't matter how late for work you are, driving it backwards to work isn't won't to get you there any sooner. So basically, as soon as something changes, time moves forward always. But that doesn't mean that there couldn't be an illusion of time reversal. For example, if we had an infinitely powerful undo button and could realign all the particles in the universe into exactly the same positions as they were at some point in the past, and recapture all the transformed energy and matter and put that back too, so that it was all perfect and exactly the way it was before, then from a practical standpoint, that universe could be said to have reverted to an earlier point in time. Although the beings within that universe would have no idea that it had taken place, you would. Because you have observed all the changes from an outside point of reference in which your clock was always moving forward.

As for gravity, we don't know enough about it yet. I tend to think that antimatter is still matter, and that gravity manifests itself wherever matter is, so it shouldn't make any difference. To figure out what gravity is, first we need to figure out what manifests it ( what imparts gravity upon matter ). Right now physicists still consider gravity to be one of the fundamental forces of nature, which is just a fancy way of saying they don't the foggiest idea where it comes from. Philosophically, it seems that to manifest itself within this universe, it must originate from someplace outside it. Therefore to build an antigravity drive, we'd either need to access whatever imparts it, or create some kind of shielding from it. I tend to think that the latter is our only realistic option to explore, and that progress might be made with further experiments in superconductivity. Years ago I got into a debate with some physicists on a BBS and challenged them to try measuring the weight of a metal disk before and after it had become supercooled. Someone eventually did that experiment and reported that by spinning the disk, they could measure subtle changes. But the results are inconclusive and more work needs to be done.

Lastly, I loved Arthur C. Clark's books when I was growing up, but never read his short stories. Thanks for the tip. Perhaps I'll take a blast into the past and see if I can find some!