Retrocausality, Time Travel, and Quantum Physics

If that title didn't bore the pants off of you, then the rest of this blog will!

The San Francisco Gate recently published an amazing article on retrocausality, which is the idea that things we do in the present go backwards in time to affect the past.

Naturally, many scientists think its silly to think you can go back in time: that would require something to go faster than the speed of light.

Plus, what about causality? Say I got my hair cut today. Then say I went back in time to yesterday to burn down my barber's place (no offense Scott, its just an illustration). Would my hair instantly grow back?

In general, this debate is between Einstein and his General Relativity fans, and the Quantum Physics fans. The former say time travel and faster-than-light travel is impossible, because that leads to incredibly weird paradoxes and a breakdown of causality.

The Quantum Physics folks basically reply, "Boo hoo! We've been dealing with incredibly weird paradoxes and a breakdown of causality for a hundred years... AND we've invented the laser, the computer, and superconductivity. What do you got?"

As you may have guessed, I side with the latter camp...

I am glad to read about a fearless quantum physics geek who may actually be able to prove time travel on a small scale is possible.

Boring physics experiments aside, the article goes into detail about the possibility that there is nothing strange at all about retrocausality. Quite possibly, time travel happens every day in small ways, and we are just not aware of it.

My hero, Richard Feynman, famously noted that a positron behaves exactly like an electron traveling backwards in time. Others have expanded on his observation with very interesting results. Perhaps these particles even go back in time all the way to the big bang, to affect the fundamental nature of our universe!

Paul Davies at the University in Sydney took this idea one step further... he and many other scientists have always been surprised at how unusually hospitable for life our universe is. If you look at how many ways it could have evolved after the big bang, its remarkable that we exist at all.

One theory is that this is nothing remarkable at all: there could have been an infinite number of big bangs before this one. If it was inhospitable to life, there would be no observer. The most recent kaboom just happened to work out well, and therefore we just happen to be around to observe it. Its just a numbers game. Fair enough...

However, if retrocausality actually happens, that means that we may live in a self tuning universe. Perhaps an unstable universe would have a lot of time traveling particles, affecting how the big bang happened, and it eventually settled down into the universe we now observe... if there is such a thing as "now".

It also leads to the possibility that disastrous time paradoxes may only exist in an unstable universe. In our universe, if somebody tried to do too much time travel, it might cause a flood of positrons to go back in time to make things more stable again... possibly by annihilating the time traveling anomaly before he does any damage.

Bad news for Dr. Who, I guess...

comments

Retrocausality, Time Travel, and Quantum Physics

You have an interresting way of wording things in your article; however you fail to display an matmatics, or elements of Quantum Physics; to back up your argument. you failed my dear sir to tell the name of so called Quantum therioist that you say has made the statement that time travel is possibel on a small scale. O! by the way when dealing with something like time travel there is no small scale. in therory just your presance or an objects apperance be just a grain of sand would disrupt the present

you sound skeptical...

you failed my dear sir to tell the name of so called Quantum therioist that you say has made the statement that time travel is possibel on a small scale

The physicist's name is Paul Davies, as I mentioned in the article. There's more long, boring math in the article I referenced at the top:

http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/01/21/ING5LNJSBF1.DTL

Enjoy!

retrocasualty

U say bad news doctor who, but if he went back in time i think that it meant that he was supposed to go back in time. i believe there is an under laying order in all things and that means if he went back the things he did would not change the future but be what made it as it is.

time going backwards

By you line of thought, what kind of phenomenon would be needed to make time start to go backwards, second by second? It's a real question. I'm writing a short film about it but need more info about it.

not quite the same thing...

Retrocausality isn't really time travel... it's the concept that some things "naturally" travel back in time to effect past and present reality.

So, like in the big boom, there were a bazillion ways that the laws of physics could have been defined, any one of them would lead immediately to chaos and disorder. However, maybe there were particles that traveled back in time that affected how the universe was formed, altering the present rules. In that sense, the first few milliseconds of the universe was chaos, filled with time traveling particles that "tuned" the universe into something stable.

Likewise, these particles may still be around... when something happens that disturbs space-time, these things travel back in time to stabilize the disruption.

How could it happen? Dunno... Ask Paul Davies.

perhaps

Perhaps "that feeling" which is sometimes telling me NOT to do certain things, or even to take a specific step in life, (which later turns out to be a "good step") is some personal proof of retrocausality.
Then again, if you experience the effect before the cause than that means that you just created an alternative reality, deleting the cause from your future reality. Or is retrocausality existing through multiple dimentia/realities?

Anyhow; It would certainly explain why mankind seems to live/lead a sort of "selffulfilling prophecy" as described/predicted in most relegions.

So.. maybe I'm just putting

So.. maybe I'm just putting this into words so I understand it better... but these particles I assume were there when the big bang happened, since they needed to have been created at some point. Even in a world of time travelling, I assume everything that exists needed to be created and start somewhere, and from there If the universe was inhospitable to them, or generally unstable or chaotic, they had the ability to go back in time before the inhospitable conditions could destroy them to change it so it was more suited to them, otherwise they wouldn't be there to go back in time to change things. For some reason I've never been a fan of the whole multi dimension thing, so I assume this is all one time line in one universe.

So.. the particle or what ever it is.. has an ingrained, automated process that makes it go back in time.. change how the big bang happened.. then return to it's original time. If indeed it exists in any flow of time at all if you get my drift. Very intriguing. I always wanted to pursue theoretical physics as a career because of this very subject but as I found out in high school and later on.. I'm not good at maths, kind of a shame really.

A Blast from the past

I remember once seeing a article in Germany that Scientist where able to send electrowaves back in time only for a few seconds-minutes

Very Good

One the 7th day God rested and saw that it was "Very Good". We are all in this together and the whole path has already been laid out. The realm of all possibilities are really only possibilities existent within the sphere of influence that we each have access to based on our individual and/or group capacity to Love. The more holistic (Love, Unity, Harmony, Cooperative, Inclusive, etc...) viewpoint of Life (which includes all biological Life on this planet) an individual, community, society, etc... maintains the more complete will be the Free Will they will experience within the Universal Creation. The further we as individuals and as societies stray (competition, strife, hostility, etc...) from Love the more negative pressure will be experienced in the present from the future "Very Good" finality. All things work together for Good -)

Quantum physics and retrocausality

According to Quantum physics, there are parallel universes... we just split to live in both of them. So how could something from one universe travel back in time naturally, and change both universes? How could something that does not exist in one place pop out before you can say "Shiver me Timbers" and change the way we are living now?
After thinking for some time, I figured out 2 theories:
1. Whenever a living thing is there to observe a result, even when it does not know it is doing so, the result will be affected to have only 1 result. (Including micro-organisms, virus etc.)
2. However, everything is a prediction: an inference, a conclusion, and even an observation. It is both true and false in a sense, but its just the place we see it in.
There's nothing we could be certain about, anything is both there and not-there-at-all at the same time.
I could have never came to this site before in the other universes anyway...

Recent comments