What Is Time? One Researcher Shares His Exploration 578
Physicist Sean Carroll has built up a bit of a name for himself by tackling one of the age old questions that no one has been able to fully explain: What is time? Earlier this month he gave an interview with Wired where he tried to explain his theories in layman's terms. "I’m trying to understand how time works. And that’s a huge question that has lots of different aspects to it. A lot of them go back to Einstein and spacetime and how we measure time using clocks. But the particular aspect of time that I’m interested in is the arrow of time: the fact that the past is different from the future. We remember the past but we don’t remember the future. There are irreversible processes. There are things that happen, like you turn an egg into an omelet, but you can’t turn an omelet into an egg."
Time is the goo... (Score:4, Informative)
that connects state one to state two.
Re:Timeline (Score:2, Informative)
Timecubist, most likely. [timecube.com] Just wait 'til he watches Primer.
Re:What Is Time? (Score:3, Informative)
Re:Time? (Score:4, Informative)
What else can you measure time against, or what else can you measure change against? Because you can measure a change in distance, a change in volume, a change in temperature, the list goes on.
As for measuring time - you can have instances where nothing changes BUT the time - so thus begs the question, what is time if nothing changes?
Imagine a single Molecule, Well if you can imagine it moving you know it has speed and then you just take the change in distance to find the amount of time that had passed.
Well, imagine if it didn't have a speed - it wasn't moving. How would you calculate the change in time?
Re:Time is the goo... (Score:5, Informative)
ding ding ding!
Time is just another dimension, but one we can only experience shallowly.
Two points make describe line.
Two lines make describe plane.
Two planes make describe space.
Two states of space describe time.
Time as we experience time in the same way a single-cell organism on a slide experiences 3-dimensional space.
Re:Timeline (Score:3, Informative)
Deja Vu isn't the same as seeing the future.
Deja Vu is when your brain screws up and you 'feel like' the thing that just happened, already happened. You 'feel like' you are recalling something from memory rather than experiencing it for the same time.
It's a 'feeling'.
Plenty of people have 'felt' Deja Vu - nobody has ever demonstrated an ability to see into the future. There is a huge, huge, huge difference between, 'Holy crap everyone - here is a really specific list of things that I know are going to happen next week that I couldn't possibly have known about without seeing the future' and 'Oh wow, I swear, I totally saw this happen before'.
Reversible computing (Score:2, Informative)
Thermodynamics is one of two sets of phenomena that are irreversible. The other [CP violation] is rather obscure
CP violation isn't obscure if you visit the seedier corners of the Internet. It's called a USB line [encycloped...matica.com]; I'll show you later.
Now imagine a computer that uses a reversible logic system that is reversible
Reversible computing [wikipedia.org] exists.
Re:Timeline (Score:5, Informative)
Anyone who says otherwise is either narrow-minded or hasn't ventured out very far into the real world.
Or maybe they have been in the real world long enough to know the truth from wishful thinking. For a while I too thought I had such powers but then when I started writing down actual details it turns out they weren't very accurate at all. I am willing to bet a good percentage of people has these fantasies but at some point you just have to face facts.
However imagine for a moment you are right:
If you think about it the ability to see into the future would be such a massive evolutionary advantage that there is absolutely no way it would remain hidden in dreams or only vaguely available. The first species to do this would dominate all others and would evolve and eventually take over all the other niches until all living species can see the future.
Secondly if some could see the future (even partially) then we would on average see more people who made such claims at the top of industries / careers as they have an advantage. Yet the people who make such claims are usually at the bottom. I'm not including people who work in the psychic industry as these are obviously frauds.
Thirdly - if some people could see the future they would be famous, and we would have positions designated within all power structures for such advisors. As things stand now we have a guy offering a million dollars for anyone who can prove it and still nothing.
Finally - in the 60's scientists were very interested in these questions and had look at every idiot of the street who made claims of supernatural powers. Nothing. Remember that scientists routinely deal with discovering things that function barely above 50/50.
Re:Time (Score:1, Informative)
Sometimes you need to just bow your head and move on. This is one of those times.
Nobody will believe you were making a joke, and you just make yourself look bad pretending otherwise. The need to look like you didn't make a mistake is understandable, but when it's so very obvious, you're only hurting yourself by belaboring it.
Re:Easy (Score:4, Informative)
It's an old comment from Henri Bergson [wikipedia.org], though his version didn't include "nature", but was instead something more like, "time is a resistance against everything happening at once".
Re:Sean Carroll's "Real Rules for Time Travelers" (Score:3, Informative)
My personal hypothesis is that either you can't change history, only fulfill it because it has already happened, or you end up in a different time line. Yay! now we have a testable hypothesis and science. We just need a way to test it.
You mean the Novikov principle [wikipedia.org]?
Re:Pidgeon dance (Score:2, Informative)
I'm on dial up so I haven't looked through much, but it looks like video is available:
http://www.google.com/search?q=skinner's+pigeons [google.com]