A Theory of Dark Matter

September 8, 2009
A Theory of Dark Matter

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Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies. The galaxies are observed in the optical (shown in orange and white). Most of the normal mass in the clusters (pink) is associated with gas heated in their collision. Dark matter is not visible, but is inferred (blue) from gravitational lensing effects; the dark matter lagged behind the other matter in the collision. The discovery in 2008, using NASA's Chandra X-ray Observatory and other telescopes, provides additional evidence for the existence of dark matter. Credit: NASA and the Chandra X-ray Observatory

Among the most astounding, unexpected, and important achievements of the past century (or even more) have been the discoveries of dark matter and dark energy, collectively dubbed the "dark sector."

A whopping 96% of the essence of our universe lies in the dark sector, where essence refers to everything that controls evolution and large-scale properties of the cosmos. Dark matter is unseen matter -- unseen in the sense that it emits no detected (light, , etc) -- but it has been definitively spotted nonetheless because its has measurable effects on stars, things that we can see. Of all of the matter in the universe, an incredible 90% is dark matter, with and stars being only minor constituents. We do not know what dark matter is, only that it is almost surely made of kinds of unlike those that comprise normal atoms.

, on the other hand, is not a form of matter at all (nor is it literally "dark" -- that is just a poetic way of saying that it is mysterious). It is the source of the outward acceleration of the cosmos, and, based on reasonable assumptions about our current understanding of elementary particle physics, may arise from the vacuum, which has quantum properties that provide energy to the cosmos. Alternatively, dark energy may be a feature of gravity that produces cosmic repulsion on a large scale.

CfA scientist Douglas Finkbeiner, together with three of his colleagues, has published a new paper in Physical Review D with a possible explanation for dark matter.

They are able to approximately describe this astonishing dark matter by making an equally astonishing proposition: the existence of a new force of nature. There are only four known forces in the world: the familiar gravitational and electromagnetic forces, and two forces whose domain is at the scale of the and are less commonly appreciated, the so-called strong and weak forces.

So far as we know, these are the only forces there are, and scientists have generally supposed that these four will ultimately explain the dark sector as well, once some additional details about particle physics are confirmed with the new generation of particle colliders.

In their new paper, the scientists build on data from five different recent astronomy measurements, most of them probing energetic regimes of astronomy, that have discovered puzzling results including a large excess of high-energy electrons and positrons in space. These particles cannot easily be explained by the conventional sources, shocks from supernova. They could come, however, from the self-annihilation of dark matter particles that, like all known forms of other matter, should come in pairs that self-destruct upon contact. Even without knowing the nature of dark matter, it is possible to argue how it ought to behave so as not to contradict other, known principles and observations.

In working out their self-consistent theory of , the scientists find that a new, fifth force of nature is implied. Although this might seem an extravagant solution, they argue that it is in fact a relatively straightforward solution, fits into a very reasonable (if novel) picture of , and fortuitously appears to solve a number of independent problems. The new ideas, if confirmed, would revolutionize our understanding of the universe. This paper, which outlines the basic ingredients of the new model, lays out a concrete first step that subsequent research can now either contradict ... or confirm.

Provided by Harvard College Observatory

3.6 /5 (44 votes)  

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Archivis
Sep 08, 2009

Rank: 4.8 / 5 (8)
"A whopping 96% of the essence of our universe lies in the dark sector, where essence refers to everything that controls evolution and large-scale properties of the cosmos."

Um... When was this proven?
earls
Sep 08, 2009

Rank: 3.4 / 5 (8)
When they told you. Either accept it or be labeled a crank.
frajo
Sep 08, 2009

Rank: 4.9 / 5 (10)
I really would like to know some of the falsifiable predictions of this new theory. But they seem to be hidden in darkness.
SincerelyTwo
Sep 08, 2009

Rank: 3.6 / 5 (5)
If the proof exists, provide it.
Baseline
Sep 08, 2009

Rank: 3 / 5 (2)
Apparently they can not either confirm or deny what this new fith force is as it seems to not have a name or description in this article.

So now to continue to try and explain away the observations that suggest that we may have it wrong, we now will require a fifth force so everything can fit?
Brando
Sep 08, 2009

Rank: 3.6 / 5 (8)
"Um... When was this proven?"

The energy/matter density of the Universe was determined recently by five years of examining the WMAP data of the Cosmic Microwave Background Radiation.
Fazer
Sep 08, 2009

Rank: 3 / 5 (2)
Dark energy is far from being proven, but I can see how a fifth, undetected, force could have differentiated from one of the four fundamental forces in a phase transition, much like the electromagnetic and weak forces emerged from the theorized electro-weak force.

So it split off and we never noticed its existence. It could happen again as the Universe cools.

In fact, I think there is another, as yet undetected, 6th force that condensed out of Gravity, oh about 10 years ago, when I was in my mid-30's. It is an attractive force that interacts with the atoms in my midsection, dragging them downward and causing unsightly, but very huggable, love handles.

I shall call it the Cellular Sagnetic force. The force carrying particle is the Carb Boson.
E_L_Earnhardt
Sep 08, 2009

Rank: 1.7 / 5 (7)
"Generous", "fair"), "unbiased", science should not cry "foul" if, (1)I suggest it predates and "creates", even "controls" the physical! One might, in accord with the evidence, say it shows evidence of INTELLIGENCE!
vantomic
Sep 08, 2009

Rank: 1.2 / 5 (6)
I think fazer is onto something...but that requires a new force as well. the atkins force can affect the carb boson.



oh and guess what fazer, your theory is as good as alexa's crap. lol
Alexa
Sep 09, 2009

Rank: 3.3 / 5 (8)
If your(anyone's) theory can explain Baron Von Richenbach's observations then it will explain Dark Whatever...

I can think about it.
http://www.hbci.c...ergy.htm
Alexa
Sep 09, 2009

Rank: 3.1 / 5 (9)
Anyway, it's interesting, how religious proponents of mainstream physics tends to "explanation" of one mysterius phenomenon by another one. Why to introduce new unknown force, if we have many other phenomena available for explanation already? IMO people naturally tend to religion in any form.
TheWalrus
Sep 09, 2009

Rank: 4 / 5 (8)
What makes you guys think your crackpot theories are more credible than the actual measurements by actual astronomers? Is there a single degree among you, or do you just like to pretend you're the "real" experts, and all those astronomers and physicists are blind to your oh-so-valuable "insights?" Get a grip.
Alexa
Sep 09, 2009

Rank: 2.9 / 5 (10)
crackpot theories are more credible than the actual measurements by actual astronomers

Come on, nobody measured fifth force directly - it's just an abstract interpetation of quite different observation.
..all those astronomers and physicists are blind to your oh-so-valuable "insights?"

Because they're ignorants in the same way, like visitors of this discussion. For individuals is difficult to accept foreign ideas and to admit, someone else can have its own truth. I have no reason to assume, people differs so much by their very nature.
JerryPark
Sep 09, 2009

Rank: 3.1 / 5 (7)
"Dark Matter" was just made up to account for the movement of stars in galaxies which are far to fast to remain bound to their galaxies according to our theories of gravitation.

It is a kludge. It is most definitely not "Among the most astounding, unexpected, and important achievements of the past century".

Alexa
Sep 09, 2009

Rank: 3.5 / 5 (11)
The experimental evidence of Dark matter is much wider:
a) Rotation Curves of stars inside of galaxies
b) Virilization of galaxy clusters
c) Weak Gravitational Lensing
d) Large Scale Structure of CMB
etc..
bowzak
Sep 09, 2009

Rank: 5 / 5 (1)
Fifth force? and... we're back to the cosmological constant. Looks like Einstein's biggest blunder wasn't including it, but abandoning it.
Tissa_Perera
Sep 09, 2009

Rank: 1.2 / 5 (6)
I cracked the DM/DE problem and not pots.
I crank out DM/DE by the ton.
It is not good news for the DM believers.
You will read what I mean
http://cosmicdark...ics.html
K. Tissa Perera
CWFlink
Sep 09, 2009

Rank: 3 / 5 (1)
I assume the real cosmologists have computed the mutual repulsive force applied upon matter by reflecting all the EM radiation that has been trapped in the universe since the Big Bang. I further assume the curvature of space created by the energy associated with this "background" radiation has also been considered. So I suspect that the balancing of these two "forces" cannot explain the observed reality. Can someone point to a tutorial which sheds light (no pun) on this?

I've always been struck by the fact a light beam is invisible when viewed from the side... yet it is clearly a flowing stream of energy. Isn't this obviously "dark energy"?

Just would like to see a reference showing that this has been factored into the discussion before I start thinking about new forces and new matter.
Velanarris
Sep 09, 2009

Rank: 4 / 5 (4)
The experimental evidence of Dark matter is much wider:

a) Rotation Curves of stars inside of galaxies

b) Virilization of galaxy clusters

c) Weak Gravitational Lensing

d) Large Scale Structure of CMB

etc..

None of which gives any insight into what "dark matter" actually is.

For all we know it's the demons of gravitation comming for their due rather than some exotic particulate.
Nik_2213
Sep 09, 2009

Rank: 1 / 5 (1)
"This paper, which outlines the basic ingredients of the new model, lays out a concrete first step that subsequent research can now either contradict ... or confirm."

Uh, would have been nice for this report to include some clue as to what their paper actually says...
Mr_Man
Sep 09, 2009

Rank: 1 / 5 (3)
My theory of Dark Matter: That shit is dark, and it matters!
Baseline
Sep 09, 2009

Rank: 3.5 / 5 (4)
What makes you guys think your crackpot theories are more credible than the actual measurements by actual astronomers? Is there a single degree among you, or do you just like to pretend you're the "real" experts, and all those astronomers and physicists are blind to your oh-so-valuable "insights?" Get a grip.


I would lean towards more than a few respondents hold degrees here. I myself hold two, neither of which applies directly to this field of debate however.

Not having a degree directly related to this field of study does not preclude one from having something to contribute to the discussion.

If the theory is sound then it should easily standup to scrutiny from a bunch of uneducated crackpots like us.
Alexa
Sep 09, 2009

Rank: 2.9 / 5 (8)
None of which gives any insight into what "dark matter" actually is..

Such stance depends on the consciousness of observer. If we would silly dogs, many (if not all) seemingly transparent things wouldn't give some meaning for us.

The question is, if we are willing to consider dark matter as a fifth force, why not to consider Casimir force as the sixth one, for example?
Noumenon
Sep 09, 2009

Rank: 4.9 / 5 (32)
There are serious problems with current cosmology that will require either more theoretical duck tape, more 'ptoemaic epicycles', ...or a revolutionary change in theory.
Nik_2213
Sep 09, 2009

Rank: not rated yet
Here's the abstract. Sorry, I don't understand much of it...

http://adsabs.har...06.3880L
Alexa
Sep 09, 2009

Rank: 3.4 / 5 (5)
Basically it's just another numerical game (N-body simulation) with quintessence (scalar field) model of dark matter/energy. In fact, it's nothing very special in this context - here are dozens of similar articles about this subject on arXiv already.
Alexa
Sep 10, 2009

Rank: 3 / 5 (4)
In 28 pages you get a extensive review of the current theory and understanding of rapidly expanding universe via cosmic acceleration. Available online for free within the first month of publication.

http://www.iop.or...6901.pdf
Velanarris
Sep 10, 2009

Rank: 2.5 / 5 (6)
None of which gives any insight into what "dark matter" actually is..


Such stance depends on the consciousness of observer. If we would silly dogs, many (if not all) seemingly transparent things wouldn't give some meaning for us.



The question is, if we are willing to consider dark matter as a fifth force, why not to consider Casimir force as the sixth one, for example?

How did you make this transition from dark matter to the casimir force? Through what observations do you base this ideology of yours.
Alexa
Sep 10, 2009

Rank: 3.1 / 5 (7)
Casimir force is supersymmetric force to dark matter deceleration, because radiation pressure is dual force to gravity. Whereas Casimir force is a shielding effect of gravitational waves at CMB wavelength distance scale, Pioneer anomaly deceleration is caused by dispersion of gravitational waves. And while Casimir force violates Newton law at small distance scale, Pioneer anomaly deceleration violates equivalence principle of general relativity and Newton law at large distance and/or energy density scale.
Velanarris
Sep 10, 2009

Rank: 1.8 / 5 (5)
Casimir force is supersymmetric force to dark matter deceleration, because radiation pressure is dual force to gravity. Whereas Casimir force is a shielding effect of gravitational waves at CMB wavelength distance scale, Pioneer anomaly deceleration is caused by dispersion of gravitational waves. And while Casimir force violates Newton law at small distance scale, Pioneer anomaly deceleration violates equivalence principle of general relativity and Newton law at large distance and/or energy density scale.

And how does the casimir force have any effect over large scales when it's barely detected at small scales?
Alexa
Sep 10, 2009

Rank: 3 / 5 (6)
We can imagine Casimir force, if we think of being bombarded from all sides by CMB photons. If another person stands near you, no photons will hit you from that side, and you likewise shield the other person. So the remaining force pushes the two of you together.

The very same mechanism works in large gradient of gravitational field, too. Because gravitational field gradient is interpreted as a vacuum mass/energy density gradient in AWT, the CMB photons of constant wavelength are losing energy near massive objects. It means, we're systematically bombarded by more CMB photons from outside space, which results into weak attractive force, which complements gravity. But with compare to gravitational force, this weak pull force depends on dielectric properties of object (i.e. ratio of CMB photons absorbed and reflected) and it's proportional to surface area projected by object in similar way, like Casimir force.
Alexa
Sep 10, 2009

Rank: 3 / 5 (6)
The shielding of CMB photons can be even observed from outside as so called SZ (Sunyaev-Zel'dovich effect. Interesting aspect of SZ effect is, some galaxies seems not to exhibit it at all.

http://www.scienc...4549.htm

Such galaxies could be composed of antimatter (which shouldn't be shielded by dark matter, but attracted by it, instead) or maybe "parallel mater", which differs form matter inside of our galaxy - this could be considered as a evidence of "parallel universes". "Parallel matter" would annihilate in contact with matter our galaxy, but not completely. We can expect many similar surprises during future research.
earls
Sep 10, 2009

Rank: 1.4 / 5 (5)
"We can imagine"

Indeed. I can imagine all sorts of stuff.
Alexa
Sep 10, 2009

Rank: 3.4 / 5 (5)
Important is, which testable predictions you can deduce from such imaginations.
earls
Sep 10, 2009

Rank: 2.8 / 5 (4)
I look forward to your experimental investigations.
Velanarris
Sep 10, 2009

Rank: 3.3 / 5 (7)
Perhaps you can give us an observation that supports your hypothesis, as well as a justification why other theories fall short of yours.

Then if possible, follow that up with a quantifiable prediction.

Imagining things is great and all but if the rubber never hits the road the car can't go.
Alexa
Sep 11, 2009

Rank: 3 / 5 (4)
Perhaps you can give us an observation that supports your hypothesis
I give it already
http://www.scienc...4549.htm
btw String theory exists more then forty years without some observation comfortably.
frajo
Sep 11, 2009

Rank: 3.4 / 5 (5)
btw String theory exists more then forty years without some observation comfortably.

Because true beauty is timeless.
Torbjorn_Larsson_OM
Sep 11, 2009

Rank: 3 / 5 (2)
Quintessence would have been interesting, but AFAIU you can no longer fit such theories to observations of dark matter in clusters cetera. (Like the nice image of the Bullet Cluster shows.) They would all come out differently, while DM gives a unique model.

And those "puzzling results" have recently been precisely "easily explained by the conventional sources" AFAIU. For example, the galaxy center asymmetry was modeled in some papers a few weeks back.

@ Archivis:


When was this proven?


The standard model [how time flies, just last year it was "the concordance model"] was IIRC supported by 3 sigma results in the WMAP 2nd data release. So that would have been adequately tested as of 2006 as I understand it.

[Then you can discuss details. There is still not enough data to test inflation at 3 sigma in isolation, I believe. So that's a task for the newly launched Planck probe. And so on and so forth.]

@ Alexa:

Aether? Aether was falsified over a century ago.
Velanarris
Sep 11, 2009

Rank: 3.3 / 5 (3)
btw String theory exists more then forty years without some observation comfortably.
This is false.

AdS/CFT connection is the obvious one, in addition to the pending high energy experiments soon to be underway at the LHC.

Grand Unification, one of the primary tests to be run at the LHC, is also a method by which String Theory will potentially be falsified.

What is your background again? You like to take shots at other people's but never explain yours.
pbfred
Sep 11, 2009

Rank: 1 / 5 (1)
There are serious problems with current cosmology that will require either more theoretical duck tape, more 'ptolemaic epicycles', ...or a revolutionary change in theory.




There is a simple, close-to-experience, "revolutionary" change that could solve the dark sector problem:



Replace the 300-year-old silly idea that mass mediates the gravitational force and with the idea that radiation emanating from mass mediates gravity.


Newton hypothesized that the mass of the sun attracts the planets. It is just as reasonable to hypothesize that it is the sun's radiation that attracts the planets.



I can heat a 210 gm test mass to 400 degrees Cecilius and place it under 3 copper containers filled with ice. A thermally isolated force sensor indicates that the the test mass has increased its gravitational mass by 22% or46 gm. For similar experiments with similar results and a gravitational theory based on spreading infrared radiation see



http://vixra.org/abs/0907
Velanarris
Sep 11, 2009

Rank: 1 / 5 (1)
I can heat a 210 gm test mass to 400 degrees Cecilius and place it under 3 copper containers filled with ice. A thermally isolated force sensor indicates that the the test mass has increased its gravitational mass by 22% or46 gm. For similar experiments with similar results and a gravitational theory based on spreading infrared radiation see
I'm intrigued, do you have a whitepaper on your experimental conditions that I may read? If the controls are rock solid, the additional mass, sans energetic excitement would stand to support your hypothesis, as well as a few of mine.
earls
Sep 11, 2009

Rank: 1 / 5 (1)
His corrected link is: http://vixra.org/abs/0907.0018
earls
Sep 11, 2009

Rank: 5 / 5 (3)
I feel a vacuum chamber should have been employed in these experiments to absolutely rule out any changes in air pressure or current.

You barely address this in your "spurious effects".
Velanarris
Sep 11, 2009

Rank: 3.7 / 5 (3)
I feel a vacuum chamber should have been employed in these experiments to absolutely rule out any changes in air pressure or current.

You barely address this in your "spurious effects".

Agreed, there are too many possible "contaminants" in this experiment.
RayCherry
Sep 11, 2009

Rank: 1 / 5 (2)
If air has mass, is Dark or Catholic?

You can not see it, but you would miss it if it was not there.

Think about it ...
Alexa
Sep 11, 2009

Rank: 3.7 / 5 (3)
...we can heat a 210 gm test mass to 400 degrees Cecilius and place it under 3 copper containers filled with ice. A thermally isolated force sensor indicates that the the test mass has increased its gravitational mass by 22% or46 gm....

This is a nice experiment, indeed - but didn't you forget hot air convection?
Velanarris
Sep 11, 2009

Rank: 1 / 5 (1)
Alexa/Slotin/Alizee/Hohnrain has developed an imagination experiment to justify his "hypothesis".

Like a thought experiment but with no basis in reality.
Alexa
Sep 12, 2009

Rank: 2.6 / 5 (5)
...is this just wild eyed speculation..

You're ignorant, who is skipping posts, because fifth force belongs between classical interpretations of dark matter - here are dozens articles about it and everyone, who is interested about DM knows about it.

http://novan.com/5th-forc.htm
http://www.physor...373.html
Slotin
Sep 12, 2009

Rank: 3 / 5 (4)
..has developed an imagination experiment to justify his "hypothesis"...
How do you want to explain fact, Pioneer Sunward deceleration (0.87 ± 0.13 nanometers/s2) agrees with product of Hubble constant and speed of light (a = Hc) in 10% error range? People know about Universe expansion seventy years already - why they never integrated it into physical theories?
Alexa
Sep 12, 2009

Rank: 3 / 5 (4)
Discussions about AWT reminds me of Bohr's cautionary tale of the farmer with the horseshoe
over his barn door.
His neighbor: "You don't believe in that, do you?"
Bohr: "No, but my friends tell me you don't have to believe in it for it to work."
Alexa
Sep 12, 2009

Rank: 4.2 / 5 (5)
Even now, two hundred years after Darwin, one half of US citizens still doesn't believe in evolutionary theory. Certain people will never accept any evidence, until they believe in opposite.
Alizee
Sep 12, 2009

Rank: 2.3 / 5 (3)
Professor Stephen Hawking has blundered by his own image... This picture is from his book "a briefer history of time" page 29 and it illustrates the energy wave spreading in particle environment.

http://www.aether...ngth.jpg

It's easy to see the waves getting further apart from each other as time increase, while Hawking is claiming, the Lorentz invariance is "difficult to reconcile" with Newton theory. Of course it is, because it leads into dark matter and expanding universe observations.

This case just illustrates, everyone sees, what he wants and Hawking, the physmatic sees waves of constant wavelength in picture, which illustrates exactly the opposite.
Alexa
Sep 12, 2009

Rank: 3 / 5 (2)
.. Darwin's theory had nothing to do with the origin of life ...
Maybe it hadn't before two hundred of years, but by now but it's used so. Now scientists are tracing the origins of life just by using of fylogenetic tree of genes. And for many people is unacceptable to think just about evolutionary origin of human species, not organic life as such.
Slotin
Sep 12, 2009

Rank: 1.8 / 5 (5)
What is your background again? You like to take shots at other people's but never explain yours.
Aether theory is very old one, it's rooted in vedian Prana and ancient greek Plenum concepts. But it took people another two thousands of years to realize, how such concept can be really working.

I presume, this is the main reason, why people are getting so upset this idea by now - it relativizes the undeniable achievement of human civilization and/or even their own IQ: "How the hell is possible, we/our scientists didn't invent it a long time before?! It must be simply wrong!"

Well, it's unbelievable - I admit. But your own reactions explains, why certain ideas can remain ignored, despite of their triviality (or maybe just because of it).
yyz
Sep 12, 2009

Rank: 3 / 5 (1)
@GPhillip, A link to the abstract (& paper) was posted above, but here is a link to the 22-page paper at arXiv.org: http://arxiv.org/...80v1.pdf .
bluehigh
Sep 12, 2009

Rank: 1 / 5 (1)
While we are taking wild guesses ...

Hyperbolic electrons have been demonstrated to exhibit a fifth force that opposes gravity. You can test this yourself. Complete details for experimental apparatus are available.

Hydrino existence has been independently confirmed in US and European labs and has been suggested as an alternative to the missing mass problem.

I am not suggesting that one theory or another explains these results but the experimental proof is there.

Sonhouse
Sep 13, 2009

Rank: 5 / 5 (1)
What makes you guys think your crackpot theories are more credible than the actual measurements by actual astronomers? Is there a single degree among you, or do you just like to pretend you're the "real" experts, and all those astronomers and physicists are blind to your oh-so-valuable "insights?" Get a grip.


What he said:) (He expressed my feelings totally. So what major pubs have any of these so-called theories been published? What predictions have been made? What observations supporting those predictions have been made and peer reviewed? It sounds an awful lot like creationists who spout their Christian dogma not even knowing or caring Christianity did not even invent their myths.
MorituriMax
Sep 13, 2009

Rank: 5 / 5 (5)
Alexa
..Aether was falsified over a century ago...
Energy can spread through particle system in two different ways: in transversal and longitudinal waves. Which way was falsified over a century ago? Which way whole world of physicists "forgot" to consider?


It was falsified by null results in these experiments:
Michelson-Morley experiment, 1887
Trouton-Noble experiment, 1903

Though falsified may be an extreme word to use, the "aether" was pretty much laid in its coffin ready for the lid to be attached at this point in time.
nuge
Sep 13, 2009

Rank: 4.2 / 5 (5)
Isn't the Casimir force a result of quantum electromagnetic field fluctuations? So how is it a new, fundamental force any more than friction? Also, isn't the casimir force per unit area inversely proportional to the fourth power of the distance? In other words, the force drops of very quickly with distance, so surely it is neglible on human scales, let alone cosmological scales.
Alizee
Sep 13, 2009

Rank: 1 / 5 (1)
Isn't the Casimir force a result of quantum electromagnetic field fluctuations? So how is it a new, fundamental force any more than friction?
It's not friction force, it's a shielding/dispersive force and under more general view all existing forces including gravity are shielding/dispersive forces too - they result from geometry of another energy waves spreading through obstacles. Dark matter can be interpreted as a shielding effect too (which is demonstrated during solar eclipse as so-called Alains effect).
Rank 3.6 /5 (44 votes)
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