Physicists observe negative mass

Off-Topic
#1

“Prof Peter Engels, from Washington State University (WSU), and colleagues cooled rubidium atoms to just above the temperature of absolute zero (close to -273C), creating what’s known as a Bose-Einstein condensate.
In this state, particles move extremely slowly, and following behaviour predicted by quantum mechanics, acting like waves.
They also synchronise and move together in what’s known as a superfluid, which flows without losing energy.
To create the conditions for negative mass, the researchers used lasers to trap the rubidium atoms and to kick them back and forth, changing the way they spin.
When the atoms were released from the laser trap, they expanded, with some displaying negative mass.
“With negative mass, if you push something, it accelerates toward you,” said co-author Michael Forbes, assistant professor of physics at WSU.”

Holy shit. This is incredible.

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#2

Someone explain the significance of this because I am a dumb 12th grader.

#3

First of all I’d probably wait until another team confirms this before we really start to buy into it.
But other than that, from what I read it’s pretty much nothing right now other than to confirm that it exist and that scientist would be able use it as a tool for looking at the potential links between negative mass and effects like neutron stars, black holes and dark energy (probably concerning their sizes in relationship to their mass and/or effect on gravity)

But one interesting thing is that I have some vague memories of once reading about a theoretical “warp engine” that would be able to travel over the speed of light but required negative mass in order to work.
It’s probably still not feasible and there are probably other problems with it (like radiation) but this find makes that theoretical design rather interesting regardless.

#4

The Alcubierre Drive. That’s actually the first thing I thought of when I saw the news, but apparently that concept isn’t validated by this discovery- apparently this study has found effective negative mass, which roughly means that quantum-mechanical complications make the substance behave as if it had negative mass even though it does not. Seemingly, that isn’t sufficient for the Alcubierre Drive to work.

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#5

Hmm interesting, thank you.

#6

You and me both :stuck_out_tongue:

But I think that is no excuse since dear @Funyarinpa is a 12th grader as well I think. :stuck_out_tongue: Tho not sure since he said his uni exams were 20 days away and the uni exams here are like 50 days away. Aaaaa theorizing.

Anyways back on topic this sounds awesome. :slight_smile:

#7

My schools’s physics department isn’t that great. It also helps that I’m more interested in Chemistry/Biology. :mariaemo:

Are those like European SATs? Sorry, I’m American.

#8

Hmmmm… interesting. Yeah I’m going to wait for the actual journal article/report before buying into anything that I read about this. From what I can tell, they made a superfluid and it did some things they didn’t really expect. I don’t know if there’s really much more to say for sure until they run some more tests and some of the sensational journalists go away.

For @Pandora, since you were curious. Basically, certain particles, which we call bosons, can, for lack of a better way to express this, get really close to each other. See, you can describe a particle with certain numbers and if a certain particle has the same numbers as a certain other particle they will repel each other. However, bosons ignore this and they don’t repel each other. This means that if you cool them way down they start to exhibit some weird-ass properties. If you are interested in some of these weird properties you should look up superfluids. Superfluids have the bizarre property of having zero viscosity. Viscosity is a measure of the ‘sluggishness’ of a fluid. Something like maple syrup has a higher viscosity than something like water for instance. However, a superfluid has zero viscosity meaning that it can flow through holes that normally it should be unable to go through. There are a load of other cool things as well.

Anyway, this kind of material, which we refer to in general as a Bose-Einstein condensate (see article) is something where we see a bunch of these bosons occupy the same state (i.e. their numbers are the same). I’m not sure what exactly they are talking about with the negative mass idea though. In general the idea behind what’s referred to above as the Alcubierre Drive is that you have matter that does the opposite of what normal matter does in terms of gravity. So most stuff warps space-time inwards and so pulls things towards it. Something with the opposite effect would warp space-time outwards and push matter away. I’m not sure if what they observed was material with that particular property. In any case, journalism covering scientific findings is always spotty at best.

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#9

Well… I’m not studying for the Turkish exam system, that’s why you might be confused lol. The exams I happen to be studying for are the APs (Advanced Placement exams- it’s an American thing where you receive a university-level course in high school and you take an exam graded out of 5 at the end of the year, you take one exam per course). I’m also in 11th grade, but that’s because I studied an extra year (as my school teaches math and science in English, we have an extra mandatory year at the beginning in which we hone our English). In a regular high school, I would be in 12th grade indeed.

@Wonderlander is from the same country as I, as I recall. The YGS (already past this year) is basically the Turkish equivalent of the SAT/ACT in that everyone takes it and it measures general knowledge- the key difference from the SAT and the like is that the YGS includes ALL subjects which means a shit ton of course load which means Turkish high school students practically bid farewell to socializing in 12th grade. Then there’s the LYS, which is later (in June) and that’s where specializations (Turkish-math, math-science or turkish-social studies) come in. Turkish universities don’t consider extracurricular stuff either, so everything becomes scoring well in the YGS and LYS.

It’s far from being anything close to an “European SAT”.

#10

Prep year ah… My laziest year in high school… I miss it <3. All that german… <3

And yeah it is nothing like SATs. Thank god it doesn’t take into account the extracurricular things or I would be in deep shit. :stuck_out_tongue: Even tho it should take them into account. Now I am in a great position tho :stuck_out_tongue: I gotta keep it in LYS too. :stuck_out_tongue:

Oooh, and maybe this is going real off-topic, if so you can answer me in PM but have you always considered studying Uni abroad and chose your high school accordingly or just… Decided in high school? :stuck_out_tongue:

And don’t even bother with YGS/LYS next year. It kills you. Especially that YGS which sucks out your soul. Don’t even.

#11

So, I looked into it a little more and asked one of my professors. Turns out it really just boils down to how you define mass. In this kind of many-body problem they define mass by the double partial derivative of E (the energy of a particle) with respect to k (the wave number of the particle). More precisely m=(hbar)^2 / {d^2 E / d^2 k} (ugh I hate typing equations like this) where hbar is Planck’s constant / 2pi. If that is the case then it is possible for a particle to have ‘negative mass’ just not how we normally think about mass.

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