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Physicists Confirm a Pear-Shaped Nucleus, and It Could Ruin Time Travel Forever (sciencealert.com)
An anonymous reader writes from a report via ScienceAlert: Physicists have confirmed the existence of pear-shaped nuclei, which challenges the fundamental theories of physics that explain our Universe. "We've found these nuclei literally point towards a direction in space. This relates to a direction in time, providing there's a well-defined direction in time and we will always travel from past to present," Marcus Scheck from the University of the West of Scotland told Kenneth MacDonald at BBC News. Until recently, it was generally accepted that nuclei of atoms could only be one of three shapes: spherical, discus, or rugby ball. The first discovery of a pear-shaped nucleus was back in 2013, when physicists at CERN discovered isotope Radium-224. Now, that find has been confirmed by a second study, which shows that the nucleus of the isotope Barium-144 is also asymmetrical and pear-shaped. In regard to time travel, Scheck says that this uneven distribution of mass and charge caused Barium-144's nucleus to "point" in a certain direction in spacetime, and this bias could explain why time seems to only want to go from past to present, and not backwards, even if the laws of physics don't care which way it goes.
Can you backup that statement? Oh wait... never mind.
the whole thing has gone pear-shaped.
Ideology: A tool used primarily to avoid the bother of thinking.
Time only "goes from" the past to the future because we define those terms by the way that time "goes", and time "goes" the way it does, from less-entropic to more-entropic states, because the process of memory formation, like all processes, necessitates an increase in entropy. Time isn't actually "going" anywhere, there are just different possible states of the universe, and the ones we we remember (or are otherwise recorded for us to gather information from) are necessarily more entropic, and we call the states we already remember (or otherwise has record of) "past" and the opposite direction in the configuration space "future".
What the hell could pear-shaped nuclei possible have to do with any of that?
-Forrest Cameranesi, Geek of all Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
Is all I got to say...
I'm not a scientist but this pear-shaped atom probably points back to the origin point of the Big Bang. It might be possible find the precise galactic center from where everything got spewed out into the cosmos?
'Cause that would be weird. Cool, but weird.
Please do not read this sig. Thank you.
It's like the sysops are say, well, they're going to discover they're living in a simulation. Change the parameters so nuclei are pear shaped, and that ought to distract them for a little while.
--Jim (me)
Can a physicist please translate the summary from journalistese into English? We're not afraid of big words here, but I can't read newspeak very well. Thank you.
someone travelled back in time to plant this fake story to throw us off the trail on our way to time travel.
How do we know time doesn't go backward? Maybe it does. We'd never know it if it did. (think about it.)
Perhaps in fact time goes back and forward all the time. This would be a nifty way to have things like spooky action at a distance. You run time forward till a correlated event happens, then run it backward and imbue the necessary future state. Instant hidden variables that you can't detect.
it doesn't matter how much time this time reversal takes since, you will never notice it happening.
Some drink at the fountain of knowledge. Others just gargle.
I do it all the time. Around 1s/s. Now, if you want to travel to the future faster, all you have to do is accelerate.
My DeLorean stocks just took a bigger hit than Brexit.
Table-ized A.I.
Just hand me $1M USD cash and I will tell you have to travel through into the future at 3600 seconds per hour. Act now wile supplies last!
My body certainly has. Maybe the atoms examined simply reached middle-age. Time* to put the universe on a diet of neutrino shakes; but they are so bland and often just pass right through ya.
* No pun intended
Table-ized A.I.
A bit off topic but the picture in TFA representing said nucleus seems to be moving even though it is not, like some kind of optical illusion. Did anyone else noticed this?
change that to "our models of physics". Just because our current models of physics don't preclude it doesn't mean it's at all possible to go backwards in time.
We simply haven't modeled it into our equations, because we haven't come up with a falsifiable test for it.
What does it mean when my girlfriend is pear-shaped? Her butt and her thighs are larger than her boobs, so does that mean she's travelling in time toward her feet?
Points to direction of next quest.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Maybe it is a watermark from the company who created OUR simulated unverse lol
Wouldn't it be hilarious that the real world company was named "Pear", and they watched astonished that their simulated universe spawned a company called Apple.
They might be wondering if there is a universal constant regarding to intelligence, fruits and technological entrepreneurship.
"And that, my lord, is how we know the Earth to be banana-shaped."
How do we know time doesn't go backward? Maybe it does. We'd never know it if it did. (think about it.)
Surprising as it seems we would actually know if time reversed because of what seems to be one of the most forgotten results of particle physics: the laws of physics do not work the same if time is reversed due to something called "T-violation": literally time-reversal symmetry violation. This is NOT the same thing as a glass falling off a table will not reassemble itself and flying back onto the same because this is an effect of entropy.
The first evidence for T-violation came from the CP-LEAR kaon experiment at CERN in 1998 [Phys. Lett. B 444 43 (1998)] and was confirmed in B-decays by Babar in 2012 (and as evidence that this result is always forgotten they forgot about the CP-LEAR measurement in this article!!). These experiments looked at how a particle oscillates back and forth between two possible states. What they found is that a particle in state A will oscillate into state B faster than one in state B will oscillate into state A. Hence the process prefers to go in one direction more than the other even though in this case the two states have identical entropy.
So if time were reversed you would be able to detect it by doing the same experiment and finding that now the particles would go from B to A faster than from A to B. Incidentally this symmetry is also closely related by special relativity to the symmetry between matter and anti-matter so reversing time would switch our universe into one which prefers anti-matter over matter and we could detect this flip again with particle physics experiments.
So amazing as it seems we could detect a flip in the direction of time and the article is just plain wrong when it says that the laws of physics don't care which way time goes: they do and we have evidence to show it!
Before the new particle, past travel could be not impossible. Now they discovered a new particle that makes it impossible. So when they discover yet another particle in the future that invalidates this no-past one, will we be back to "maybe possible"?
Slashdot, fix the reply notifications... You won't get away with it...
I'm pretty sure Bill and Ted's Bogus Journey already ruined time travel forever.
You are welcome on my lawn.
Time travel has been over used and generally poorly done. Hopefully this kills it.
Several Sci-Fi genre relied on gravity not being bound by the speed of light. LIGO has killed that.
It will be interesting to see where the hard sci-fi authors go now.
Oddly enough Edgar Rice Burroughs is still sorta safe, since his Mars is in an alternate reality (other obvious failings aside).
even if the laws of physics don't care which way it goes.
Lacking access to a good intergalactic physics lawyer the Human race continues to make it up as they go along.
Imagine navigating the U.S. Justice system by trial and error the way science has been doing it.
The Volgons at least had a printed manual, in triplicate, read as poetry by some Volgons in self defense.
~ People that think they are better than anyone else for any reason are the cause of all the strife in the world.
Time only "goes from" the past to the future because we define those terms by the way that time "goes", and time "goes" the way it does, from less-entropic to more-entropic states
Actually that is not true because of something called T-violation which has been observed in kaon and B-meson oscillations (see my other reply to a post below for details but this is NOT an effect of entropy!).
What the hell could pear-shaped nuclei possible have to do with any of that?
This is harder to explain and you are absolutely correct that the article utterly fails to do so! We have three special symmetries in particle physics called C, P and T where T is time-reversal and C and P together, CP, is the symmetry between matter and anti-matter. What relativity tells us is that all three together, CPT, should be a perfect symmetry of nature. This means that CP (the matter-antimatter symmetry) and T (time reversal) are linked because if the T symmetry is violated then the CP symmetry must be violated in exactly the opposite way so that CPT altogether is conserved.
Now the pear shaped nucleus is interesting because the nucleus is bound together by the strong force and every test so far suggests that the strong force obeys C, P and T separately (and so of course also CPT together). The weird violation of T and CP is only seen in the weak force (which causes nuclear beta decay). Now if a nucleus has a non-symmetric shape it suggests that the strong force also violates P, called parity. If P is conserved then if you flip the direction of the x, y and z axes there is no change. However with a pear-shaped nucleus there would be a change and so parity is said to be violated and this means that CP would also be broken.
So, if true, this result would be interesting because we have never seen this effect in the strong force despite it being possible to add a term to do this and it has always been a mystery as to why this term appeared to be exactly zero - it is called the "strong CP problem". Since CP is tied to CPT by relativity this means that we would expect time reversal to be broken as well by the strong force. However despite the BBC's best effort to advertize Dr. Who this result says absolutely nothing about whether time travel is possible just that time seems to have a preferred direction...which we have known since 1998 thanks to the CP-LEAR experiment.
As for the "pointing in the same direction in space" I want to see that written in a journal before I give it any credence. Given there are several errors and mistakes elsewhere in the article I the journalism behind this story is seems appalling and I think they completely misunderstood the explanation given...which as you can see above is not exactly trivial!
... with the pear shape, but does it become saggy over time? Can we make implants to restore or even enhance this shape?
... you make the rockin' world go round.
*All the nuclei must point in the same direction!*
“He’s not deformed, he’s just drunk!”
It says nothing about "pear shape".
If they all point in the same direction could this lead to a type of space compass that could be used for very precise navigation of where we are in the universe?
If someone can circumvent the first or second law of thermodynamics, they can call themselves a deity for all intents and purposes.
How can something physically point to an abstract like time?
Like, holy shit guys, this thing is pointing left..that's the past!!! Yeah man, they're all pointing left..whoa!!
I cannot imagine how the orientation of a physical thing can have any correlation, whatsoever to time. Someone please explain this.
A particle traveling forwards in time is (before this research, anyway) mathematically identical to an anti-particle traveling backwards in the time dimension. Historically, we've assumed that you could reverse all the velocities of the particles in a system and it would behave exactly as if time was going in the opposite direction. Showing that this is no longer strictly true does not necessarily mean that the universe doesn't consist of a 4D chunk of space-time which you could travel though using magical technology and make changes which propagate forward according to rules that are just vague enough to prevent infinite recursion. However, not too many people know how significant an exception to time-symmetry is, so I guess they have to make do with the closest widely understood concept. I wouldn't find this so annoying if it weren't for the fact that there are many fields of science which I don't know enough about to know to what extent they are getting creative with the press releases.
http://phys.org/news/2011-04-s...
I think until the majority of scientists do not accept this we won't have a unified theory.
Even Lee Smolin acknowledges that we have some problem with time (in The Trouble with Physics), but he thinks the problem is that we treat time as a static/frozen thing while he thinks it is a dynamic thing like space itself (eg. the shape of space continuously changes due to matter).
Government cannot make man richer, but it can make him poorer. - Ludwig von Mises
While the pear shape discovery is interesting, the time asymmetry implication is nonsense. The fact that an equation is symmetric does not imply that the solution must be symmetric, just that applying the symmetry to the solution must also be a solution. So the result is compatible with time assymmetry but in no way proves it. Nor does it in any way imply that the direction the nucleus points to has any special meaning. Also notice how we didn't conclude there was a special axis to the universe from the disc shaped solutions...
Is it that ALL the nuclei in the universe point in the same direction, and never move? I don't think so, so why should they identify a privileged time direction?
Instead of this being a CPT violation that requires all of physics to be "rewritten" there is another possibility that I hope they will look into.
Just like a finely balanced wind-vane (weather-vane) that can be moved around by the slightest breeze, might it not be the case that these particular isotopes (proton+neutron combinations) result in a unique very delicately balanced system that becomes "sensitive" to the movement and flow of other smaller matter/energy movements which can thus result in the apparent imbalance in shape?
For instance; if the nuclei of these isotopes are able to be influenced by the flow of a large enough number of neutrinos (for the sake of an example) traveling with sufficient energy then that could cause a wind-vane effect wherein the nuclei would be deformed in the direction of the neutrino flow, or perhaps the opposite? (btw: If this is the case then we now have the ability to build cheap neutrino detectors, or detectors of whatever is causing this.)
I sincerely hope that this idea is brought up with the scientists involved with these discoveries so that it can be investigated.
Yet another article that takes massive liberties with pure speculation and has almost nothing to do with science other than the word scientist.
My $0.02 will always be worth more than your â0.02, so
Apple shaped ones are generally more attractive but they are beset with health problems and decay quickly. The ugly pear shaped ones are the ones still extant.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
balance and atom of Barium-144 on a pin and depending on the direction it's facing you can always know what direction is "universal north"
Sure we might not understand why, but neither did the folks who used the first magnetic compasses.
So the strong force is leading the weak force in time/space causing these two force states to smear in time and space. The pear shaped particle strong force is waiting for the weaklings to catch up. Or, the weak force is leading the strong force since the weak force is lighter and more mobile and the strong force is slow lump that takes its time to catch up to the weak force..... :)
If some particles hint at a direction in time and other particles do not then maybe only certain particles have a direction in time. Perhaps other particles have a bias in other directions. Also it may just be that a time bias exists as a very local condition and implies nothing for the rest of the universe. Somehow my suspicion would be that since we know that we are headed for a certain black hole that a directional bias might just be towards that black hole. But then again it is all well beyond me.
The text in both the article and the slashdot section are enourmous. It's CPT Charge Parity Time that is conserved and T stands for Momentum not time! the article seems to ignore this fundamental fact and draws a strange conclusion. However, I need to find the real scientific article to know what is being said hear, because we KNOW in physics that time tends to move in 1 direction and that moving backwards though possible is rough. I do not see how something to do with CPT would affect time, dark matter perhaps but time? That would break down fluid dynamics (aka how we fly planes) and GR aka General Relativity! I need to find the orginal article after work today... I think a journalist ran amok and reported a really cool discovery of pair shaped nuclei all wrong.
Hey Richard Feynman --- yeah I hear you laughing, we've been snookered again. It doesn't sound like a downer at all. If we're capable of perceiving that some of these things aren't just 'are' ... they are 'are' yet they are also 'oriented' ... that means we have been given a Signpost to follow ... and we must follow it.
Never mind that time travel blather. All fixation on 'practical time travel' in physics is a rollover from science fiction, in which it exists solely for humans to go back in time to fix::notmake their stupid mistakes and get the girl, this time. It's all about getting the girl. Modern girls don't want to be part of your strange loops, they prefer to get 'got' the first time around by guys who have just figured out the best way to get ''em.
Let's move on to the real question: what does this upset to physics imply, if anything,to the possibility of stable fusion containment...? Help, hinder, harness? That's the girl we want to get.
Finding asymmetric nuclei is like discovering that you can put batteries in a toy you got for Christmas. And it's July. So put 'em in and let's see what this thing really does.
<blink>down the rabbit hole</blink>
General Relativity will buckle. The point at which General Relativity will buckle is the speed of light in a vacuum.
Space-time curvature is a creative theory, but there it will remain forever.
But if laws are not symmetric, then your brain will not work the same. You will un-learn and then un-do the experiments, so you will not be able to reach conclusions.
You are missing a few important details here. First, as far as we know, this time reversal asymmetry does not apply to the EM force which is how our brains work so they would not be affected. Second the effect is a tiny one only measurable with extremely precise experiments so you would not notice an effect without detailed experiments. Lastly though "unlearning", glasses leaping back onto tables etc will only happen if you rewind time, not just reverse the flow i.e. force everything to return to its precise, previous state rather than reverse time and let the universe evolve naturally under it's physical laws. The two are completely different questions.
Nothing but you have not reversed time you have rewound time and forced everything to go back into the precise state it was in just before. That is NOT the same as reversing the arrow of time. To reverse time you have to let the universe evolve naturally under its own physical laws just now with time counting down rather than up. Essentially all you do is put a minus sign in front of the time and ask whether everything will happen the same with time now going in reverse...and it will not.
Rewinding time is completely different because in that case the only physical law is that you must return to the fixed state you were in just prior to this one. This will erase all knowledge of what is now the past (because our current state has no knowledge of the future) and there are no real physical laws because everything is predetermined.
A few years from now someone will "discover" something that disproves the limitaion of the pear shaped nuclei. The one thing about science, it's never certain, and what we thing is fact today, becomes fiction tomorrow. " Fifteen hundred years ago everybody knew the Earth was the center of the universe. Five hundred years ago, everybody knew the Earth was flat, and fifteen minutes ago, you knew that humans were alone on this planet. Imagine what you'll know tomorrow. " K, Men in Black.
"Imagination is more important than knowledge" - Einstein
Ba, neutrino shakes. Only three tastes, and you can't even be sure it hasn't changed on your drive home from the store.
int main(void) {while(1) fork(); return 0;}
As usual we have no clue what the universe really is. But pretending we already know it all.
This all sounds consistent Shape Dynamics. IANAP, but according to Lee Smolin's book Time Reborn, this can lead to a preferred frame of reference, including an actual centre of the universe. It also make time into its own thing, disentangling it from space. Which could ruin time travel forever.
You will not drink with us, but you would taste our steel? - Walter Matthau, The Pirates
Then maybe, just maybe, there's a possibility that we will find nuclei on a cob.
What a pear-shaped loser!
People still think that time exists ? Walks off chuckling whilst shaking head.... Poor deluded humans....
Most people want a six pack, I have the whole keg!
I worked really hard getting in the shape I am, pear is a shape...
APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
This used to be my field of research as a postdoc in the 1990s, and this research was done at the lab where I worked then. The slashdot summary seems wildly inaccurate compared to the actual claims in the paper, which you can see here without a paywall: http://arxiv.org/abs/1602.0148... . I can't tell whether Scheck, who is one of the coauthors, is really making these overly gee-whiz claims, or whether his remarks have been taken out of context and distorted to an incredible extent.
This is an example of an effect called spontaneous symmetry breaking, which is well known in particle physics, molecular physics, and nuclear physics. An example of SSB is when you balance a pencil on its tip and it has to pick whether to fall to the left or the right. When a molecule such as H2 forms, it has to randomly pick a direction in which to orient itself, and this is also an example of SSB, which breaks the rotational symmetry of space. For an asymmetric molecule such as H2O, there is also a breaking of reflection symmetry. In nuclei, SSB of rotational symmetry has been very well known for a long time, because many nuclear are football shaped. What's more recent is that a few nuclei have been found that are pear-shaped, which gives SSB of reflection symmetry. As the paper admits up front, this work is not actually the first example of this kind.
The stuff about time travel is just nonsense. Anyone who wants to learn more about this kind of physics can google phrases like time-reversal asymmetry, arrow of time, closed timelike curve, and Jahn-Teller effect. This experiment does not have any new implications for the arrow of time or time travel.
Just point the nucleus of Barium-144 in the direction in spacetime you wish to travel.
Must have gotten that way from sitting too long and drinking too much beer...
Paul E. Bahre
Farmers around Chernobyl discover nuclear pears all the time.
Star Trek transporters are just 3d printers.
Time does not "flow", it is we who move though it. And there is little evidence that we move together, or even in the same direction ...
https://www.youtube.com/watch?...
The nuclei point "in a particular direction", whatever that means. If they all point in the same direction that would certainly be interesting, but it's not clear.
Thank you. All pear-shaped objects, even pears, "literally point towards a direction in space." TFA utterly fails to explain how one can then make the leap to saying this proves "there's a well-defined direction in time and we will always travel from past to present".
But as an aside, if the arrow of time suddenly did reverse, think how odd that would be to experience. We wouldn't be able to see, because photons would be exiting our pupils instead of entering them; we would literally be "un-seeing" sights and unthinking our thoughts. We would walk backwards into concert halls in order to un-listen to musicians. Our emotional states would be the result of things that haven't happened yet. Educated people would become de-educated. Graves would be un-dug; aborted fetuses would spring back to life, and the arguments about whether it is ethical to abort them would be un-had. The "undo" command on every computer would effectively become a "do" command. Later, those computers' operating systems would be uninstalled, and then they would be un-manufactured.
When time runs in that direction, everything seems rather pointless, does it not? It seems that there's a good reason time does not run in that direction.
That that is is that that that that is not is not.