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Intergalactic Missing Mass Missing Again
Ponca City, We Love You writes "Researchers at the University Of Alabama In Huntsville have discovered that some x-rays thought to come from intergalactic clouds of 'warm' gas are instead probably caused by lightweight electrons — leaving the mass of the universe as much as ten to 20 percent lighter (in terms of its ordinary matter) than previously calculated. In 2002 the same team reported finding large amounts of extra 'soft' (relatively low-energy) x-rays coming from the vast spaces in the middle of galaxy clusters. Their cumulative mass was thought to account for as much as ten percent of the mass and gravity needed to hold together galaxies, galaxy clusters, and perhaps the universe itself. When the team looked at data from a galaxy cluster in the southern sky, however, they found that energy from those additional soft x-rays doesn't look like it should. 'The best, most logical explanation seems to be that a large fraction of the energy comes from electrons smashing into photons instead of from warm atoms and ions, which would have recognizable spectral emission lines,' said Dr. Max Bonamente. The work was published Oct. 20 in the Astrophysical Journal."
Intergalatic? Say what?
As light fans out, it does so at the rate of 1/r^2. Double the distance, and you've quadrupled the surface area of the light beam. You've also reduced the luminosity at any point in the beam's surface by a quarter.
But why do we just assume that gravity needs to fall off at the same rate as light?
a warm gas. (and lightweight electrons.)
cat sig >
So who didn't look under the couch???
Understanding the scope of the problem is the first step on the path to true panic.
is the obesity problem over then?
The other, slightly less, logical explanation is that the difference in mass can simply be explained by the number of missing ballpoint pens in the universe.
GALACTUS!!
The best, most logical explanation seems to be that a large fraction of the current theories put out are similar to the remaining fractions in that they are all delivered out the little brown holes of out-of-control modern astro-theoreticians.
there must be another dimension, connected to the dryer vent
are you from the time cube?
Conservation of Mass and America's obesity problem better explain where it has disappeared to.
Letter To Iran
But we 1/r^2 is a good approximation for any gravitational fields near us.
Yes, 1/r^2 it works pretty well for relatively short distances but it may not be so for long distances. Which is the reason that some physicists don't think there is any missing mass (dark matter) at all and that both GR and Newtonian physics may need to be revised (GR uses Newton's G). This would create all sorts of problems because it would also bring other matters into question such as the supposed accelerated expansion of the universe. The Einstein fanatics and the Big Bang proponents refuse to consider it as a possibility (a lot of careers depend on Big Bang and Esintein being right). Einstein is a demigod in some circles and his wisdom must not be questioned. As a result little funding is allocated for research in this area. That's too bad. We are probably missing some very exciting physics in the process.
Please. It really isn't hard to show that the dependency on r can only take on a few values and still yield a universe that comes at all close to what we observe. For example, the only halfway-plausible power of r that allows closed orbits (such as planets around stars) in classical mechanics is exactly 2. All other values either don't allow closed orbits in general, or are trivially shown by experiment to be absurdly wrong. Now, we have observed that orbits aren't exactly closed (the most famous example being the precession of the perihelion of Mercury), but these were explained astoundingly well by relativity.
Astrophysics is way beyond getting the growth rate of a fundamental force wrong.
Its probably just a rounding error, that's what happens when you set Pi = 3
I can understand the universe being lighter, but its mass being lighter?
Now, back to my new computer that has a faster speed yet runs at a colder temperature. I'm going to move its location, which will require a longer length of Ethernet cable. Hopefully this farther distance from the router won't be a problem.
Based on nothing more than pure speculation, I believe the missing mass of the Universe is tucked away in all those little tiny extra dimensions at the planck scale of things.
Of course I'm wrong but hey - this is Slashdot.
Shh.
US Consumers Clueless about Missing Intergalactic Mass
...
"A study on consumer perceptions about missing intergalactic mass, undertaken by the Asimov Institute at the University of Phoenix Online and the Speilberg Space Policy Center, found that the average American consumer is largely unaware that some x-rays thought to come from intergalactic clouds of 'warm' gas are instead probably caused by lightweight electrons. Those surveyed showed little knowledge on the extent to which the mass of the universe was previously calculated. More than half of those surveyed -- about 55 percent -- falsely assumed that large amounts of extra 'soft' galaxy clusters were actually a light chocolatey candy.
July 2000 - Maintenance cleaning on the dish (by John) December 2000 - Damn squirrels, cleaned some surface of the dish (by John) May 2001 - Checked dish, seems to be clean (by Sir John) December 2001 - Dish seems to be clean (by Captain John) January 2002 - Sandstorm hit, sandstorms in January? heck, I'm going on vacation (by Admiral John) December 2002 - Cleaned the dish, had a hard time with the dust, now i remember.. (by Senator John) ...
July 2004 - Cleaned the dish (by Emperor John) ...
July 2007 - Cleaned the dish and polished it, why do i need to polish it? (by Galatic Emperor John) ...
Maybe it's me, I'm sure it is just me, but lately it seems that there is more lost and found mass in universe than files in a system? Maybe it is more difficult subject? I'm waiting when they get the final numbers out, I'm still under 1000 years old.
What?
Is the galaxy on the same diet as Oprah?
Have gnu, will travel.
So, does this mean that their is more dark matter in the universe to make up for it, similarly less dark matter, or that the same amount of dark matter is still supposedly out there?
Those darn scientists can't keep track of anything. How can we expect them to solve little problems like global warming when the can't even keep track of 10 to 20 percent of the universe. I bet they haven't looked under the couch.
I realize this is offtopic, and will be modded down as such, but it grates on me when I see a perfectly good flame modded down as flamebait. Flamebait is something that attracts flames. Flames are what feed flamebait. They are not synonymous.
Flamebait is characterized by the deliberate use of directly flame-able content. "Hi! I'm an Apple user, but I don't accept the gay lifestyle. Is there anyone way to fix one or the other problem?" Note that the comment uses the commonly repeated fact that Apple users are mostly gay and that he positions himself as the opposite of it. Then he insinuates that being an Apple user and gay are problems. He asks for help, but there is no way to answer without either claiming that Apple users are gay, that Apple computers shouldn't be used, or just starting over from the beginning and laying waste to his initial premise. The final choice, which is the obvious one, is almost always in the form of a flame. Thus, the flamebait post worked and garnered the flames he intended.
The reply comment which flamed him is not flamebait though, unless it also deliberately uses flame-able content. Mostly, these flames are useless and should be modded off-topic.
To sum up: Don't mod flames as flamebait. Mod them, if anything, off-topic.
Comment removed based on user account deletion
...measuring the mass of the universe when we still don't know how many angels can fit on the head of a pin? :o
The growth rate could be proportional to 1/r^2 on a galactic scale, but diverge from that on an intergalactic scale.
I think everyone throwing out 1/r^2 needs to really think about what it means. You don't need to be a hyperphysics guy to sort this out. The idea is really simple, is that, if you have a point source of some effect, radiating out equally in all directions, its effect would diminish as to the square of the distance. This "law" is really just a model that's a consequence of two things - one is that the source of the effect is essentially a point for purposes of calculation, and the other is that the effect is equally distributed over that area.
For gravity not dissipate over 1/r^2, then, it follows that in any of those systems that the distribution is not geometrically uniform. From there, we have to ask ourselves, well, why could that be?
1) It could be that gravity is not exactly a point source... or, to put it another way, that even over a cosmological distance, a gravity well is not evenly shaped. Thus, the force of gravity 90 degrees around and 2 light years from a point source is different from the force of gravity at 270 degrees around and 2 light years from the same source because the point is not actually a point, and a distance where it matters.
If not a point then? Then what shape would you choose? And you do have to choose carefully as there is an aweful lot of experimental evidence that says a point source indeed works 99.99% of the time. Here comes the heavy math. All math is, in physics, is a tool to describe the shapes of things. I'm not a math guy, but the gist of relativity is that Einstein used a new kind of math to describe curves in multiple dimensions to describe how space and time interact. Hooray for Einstein!
So, if you are that smart, with that formula of yours in mind that describes the new geometry of gravity, you ought to be able to observe it. You should be able to see telltale signs of it in the orbits of our planets in our solar system, unless your gravity formula predisposes a mixture of mattter or scale outside of what's in our system. But then, astronomy can help you, as, you can point a telescope anywhere and find some sort of a signal that matches your prediction. If that were the case, then you would be hailed a hero.
2) Gravity is amplified and or dissipated due to some unknown interaction with some other gravity "field", or some other sort of matter. Here again, you'd need to break out the heavy math and find some sort of a model that covers everything we do know is true about gravity, which is a lot, and then tacks on your stuff at the extreme. With that model, you can again then devise experiments to test it.
In both cases, notice that there's no conspiracy involved. Instead, to do physics, you basically just
a) have the insight and imagination to see what is going on in the world.
b) have the mathematical tools to describe that vision consistent with all else that is known for "sure" about physics.
Neither a or b is particularly off limits or even banned by the masses from obtaining. Many people are just born with a), and b) is something that you get if you are willing to dedicate yourself to getting a Phd in physics. Otherwise, you can't really make a contribution that's meaningful. You need the math to describe what you are talking about, in a -useful- way, and you need the knowledge of what's already out there so that your math doesn't fall flat on its face when someone points out that your theory of gravity, if applied, would mean that people could just jump off the earth into outer space.. and you have to go back to the drawing board because you don't know what you're talking about.
This is my sig.
All any so-called crackpot needs to do, to prove his or her alternate theory of matter correct, is to build his or her anti-gravity machine, reverse the flow of heat from cold to hot, or do something simple and repeatable that shocks us into a new way of looking at physics. If entropy is wrong, gravity is wrong, electricity is wrong, then, let's see the new gadget that proves it. Or, barring that, point to the heavens and make a prediction about something we haven't seen before, and do so with math that is consistent with the math that we already have. The steps are there.
This is my sig.
It's strange that, when I first read this, there was a Disney ad underneath about "making magical connections".
"lightweight electrons"????
For God's Sake! There really was nothing wrong with Bohr's atom was there?
I'm still trying to explain wave and particle theory to my pug dog, who gazes intently into my eyes!
Now I've got to try and explain electrons that don't 'weigh'(?) as much!
Don't be apathetic. Procrastinate!
No .... I believe that may be the Wisdom Cube's cousin, the DumbAssATron.
The mighty lord god for he hath great humour and wit. God Now you see it, now you don't, now you see it, now you don't, ha ha ha I kid myself"
...when the missing mass (plus or minus) gets down to about 3 tons, and the search is concentrating on unmarked landfills; THEN I'll care. I may even get obsessive.
Anyone else having trouble with the comparisons of aircraft carriers to fireflies, wondering why "bump" in the data has quotes around it? I'll let them keep the snowy fence post as a freebie.
Speaking of which google says proton mass / electron mass = 1,836.15266 so since when did an aircraft carrier weight as much as 1,000 fireflies anyway???
proton mass = 1.67262158 x 10^-27 kilograms
electron mass: 9.10938188 x 10^-31 kilograms
aircraft carrier mass: 9 x 10^7 kg (88,000 metric tons for a big one)
firefly mass: 2 x 10^-3 kg (what a grasshopper supposedly weighs)
snowflake mass: 3 x 10^-6 kg (typical 100 crystal snowflake)
So if proton/electron is about 1836 then we should be talking more about aircraft carriers to trucks, or to make electrons seem wispy we could compare fireflies to snowflakes. If you want to tell people about science you shouldn't use metaphors that give them wrong concepts.
The puzzle to explain the missing mass may well fail until physicists, whose explanations depend upon a "dead" universe, evolves to encompass the fact that the universe may well have made a "dead" to "live" transition, and therefore a "physics controlled" vs. "intelligence controlled" transition sometime a few billion, but perhaps as much as 6-8 billion years ago. This is documented by Lineweaver's group in dealing with the fact that most of the Earths in our Galaxy are *older* than our own. We are the latecomers. Until the physicists wake up to this fact everything they are spouting is suspect.
Until physicists and astronomers incorporate ideas such as Dyson Shells or Matrioshka Brains into their thinking (and seek to prove or disprove them) then all of the speculation about dark matter is just yada yada yada. The dark matter can easily be explained by Matrioshka Brains who have left their galaxies.
The universe has intelligence in it (we being the case in point). Unless theories about the evolution of the universe incorporate theories about the evolution of intelligence and civilizations they are clearly missing part of the equation.
That's probably a typo, it should say intergelatic. That's something between ice creams.
Props for commenting with a Aqua Teen Hunger Force reference :D
- Mad, ingenous - they've both left you puzzled -
1/r^2 is invented as per intelligent design. Otherwise, playing soccer in the heavens is a dread burden, fetching that ball back every time and again.
With great power comes great electricity bills.
Leave Rosie O'Donnel out of this. All of her. Completely out. Please.
This proves that science is completely wrong (again) and should never be trusted. Oh yes, and the earth is 5000 years old.
I don't have time to read the paper at the moment, but the soft X-ray excess issue has been hotly debated for a while now. Basically, people keep finding what they claim are non-thermal soft emissions in various clusters, and other people keep showing (or trying to) that it's an instrumental effect, or improper calibration, or similar. Unfortunately, while the current generation X-ray instruments have done some fantastic science, they've had far more calibration issues than one would desire, and so debates like this keep happening. At least it leads to some fun (to watch) exchanges at conferences.
To lose the intergalactic mass once might be considered a misfortune. To lose it twice begins to look like carelessness.
You know what they say about opinions. They're all fabulous!
But the real comedy is the fact people want to try and fathom the mass of something incalculable. And these are scientific minds! LOL
The parallel would be if religious nuts tried to calculate the mass of God.
The dangers of knowledge trigger emotional distress in human beings.
...and it said it was only going out for a pack of cigarettes!!!
There's a known MacOS X 10.5 (Leopard) bug: if you attempt to move some mass between two galaxies and the destination galaxy becomes unavailable during the operation, then the mass just disappears altogether. Poof!
nitrous oxide is dangerously cold when it's expanding from a capsule.
Medium cat is MEDIUM.
- Electrons are negatively charged. How do you inject a massive charge into this gas without messing up the models big time? You still need the heavy protons to balance the charges.
- If the gas accounted for 10% of the total mass, how can getting rid of that component change the mass of the universe by 20%?
From reading the paper, Table 5 seems to be the most relevant. They model their data using different interpretations: uniform warm gas, filamentary warm gas and hot plasma. If the soft X-rays are being generated by inverse Compton scattering of cosmic microwave background off of the hot plasma's electrons, then you can work out the density of the plasma. They list 2.4×10^-3/cm^3, as opposed to the (presumably orthodox interpretation) warm gas model having 3.3×10^-3/cm^3 in the hot gas plus 1.3×10^-3/cm^3 in the warm gas, which is about a 50% difference.So if this component was thought to contribute 10% to the overall cluster mass (as postulated in this guy's previous paper A massive warm baryonic halo in the Coma cluster), then this knocks that down to 5%. The paper doesn't even bother mention this, but instead focuses on the change to models of chemical abundances. Apparently, their new model pushes heavy abundances up to Solar levels; they had been lower using the old model.
As best I can tell, baryonic mass for the universe should be about 30%. The warm gas was thought to be 30% of that, or around 10% of universal mass. So knocking this down is really a problem (though garbled in the press release). Perhaps this lends support to a MaCHO component of galaxies?
Oh yeah? Prove it.
God, what an idiot.
Lost near Andromeda galaxy. Responds to "Cuddles". Call 555-5432 with information. $50 reward!
First the newly proven 2,3 Turing machine reverts to its previous non-proven status, and now the intergalactic missing mass is missing again... my life is getting turned upside down. What's next, them telling me my 1200-sq-foot Palo Alto home has started depreciating and is no longer worth the $2M I owe on it?
- First they ignore you, then they laugh at you, then ???, then profit.
Did anybody think to look under the sofa cushions?