Posted on 04/25/2019 7:37:31 AM PDT by Red Badger
One of Stephen Hawking's most famous theories about dark matter — that this mysterious and invisible substance is made up of primordial black holes — recently suffered a huge blow. That conclusion comes from a massive telescope that captured an image of an entire galaxy in one shot.
The findings don't completely rule out Stephen Hawking's famous notion. But they suggest that primordial black holes would have to be truly tiny to explain dark matter. Dark matter mystery
Dark matter is the name given by physicists to explain a particularly mysterious phenomenon: Everything in the universe moves, orbits and rotates as if there were more mass than we can detect. Explanations for dark matter range from ghostly particles called neutrinos to unknown particles, to new laws of physics. In the 1970s, Stephen Hawking and his colleagues theorized that the Big Bang may have created a large number of relatively small black holes — each about the size of a proton. These tiny, ancient black holes would be difficult to see, yet would exert a large gravitational pull on other objects — the two known properties of dark matter. [The 11 Biggest Unanswered Questions About Dark Matter]
Until now, this theory could only be tested for primordial black holes heavier than the moon. But as technology has improved, scientists have been able to take sharper and sharper pictures of outer space. The Hyper Suprime-Cam (HSC) digital camera on the Subaru telescope in Hawaii is an advanced piece of imaging technology that can take a picture of the entire Andromeda galaxy (the nearest galaxy to our own) in one shot. Masahiro Takada and his team at the Kavli Institute for the Physics and Mathematics of the Universe in Japan used this camera to search for primordial black holes;
(Excerpt) Read more at livescience.com ...
This is certainly unsettling science. I thought Hawking knew it all.
Yeah I’d like one, but the repair costs are astronomical- beyond what I’m able to afford sadly- friend just did a partial exhaust replacement for a fella and it cost over $1500- just had mine done, on my toyota, for a few hundred- which while still more than exhaust for domestic vehicle,s was much more reasonable than a subaru exhaust replacement
No comments noted from Cal Tech physicists Dr. Sheldon Cooper, Dr. Leonard Hofstadter, astrophysicist Dr. Raj Koothrappali, or Mr. Howard Wolowitz, from the Engineering Dept.
As I recall Hawking’s theories on black holes, small black holes would evaporate in relatively short time spans so any tiny, primordial black holes would be gone now. The jist of the theory is that energy fields in space will spontaneously generate particle/anti-particle pairs. In relatively flat space those particles will naturally be pulled back together and annihilate each other but at the event horizon of a black hole one could be pulled into the gravity well while the other could escape. This would lead to a slow loss of mass from the black hole if there is not enough mass in falling to make up for what is being lost. A smaller black hole or a black hole in a large empty space (i.e. between galaxies) cannot attract as much new mass to replace the mass being lost and therefore would slowly evaporate over time.
Have you ever read Stanley Jaki’s “The Savior of Science”?
I just watched something the other day, believe it was on Science channel, discussing the Universe as a hologram theory...
The math behind it, seems to answer the dark matter problem, in that there is no such thing, the “extra” gravity is simply a matter of how we perceive the hologram. It also appears to unify (at least at the mathematical level) quantum and newtonian physics.
Obviously the whole explanation was dumbed down so a simpleton like me could follow it, but it appears as more and more people are theorizing and exploring this theory the more and more sound it seems to be becoming.
It even can explain the “loss” of information when matter enters a black whole... and while I admit I didn’t grasp all of it, it seems to imply that entire holographic universes could exist inside a black hole, and you could extrapolate from that, that our universe may be the inside of a black whole of another universe.
No wonder Physics grad students all smoke pot.... The stuff they come up with is mind bending.
You can get the same effect from playing Black Sabbath at 78 speed..................
Nah, that’s more of a Chipmunks on Acid sound than mind bending
The dark matter is between their ears...
In any event, physicists are working through the possibilities and in time will figure out the problem.
“What is it?”
The famous atheist suffered a huge blow when he died too. Terrible blow.
Just thinking this through, an event horizon would grow from a smaller point. That means it would expand outwards past such matter, which would from the observer’s perspective always be trapped on the event horizon. IIRC, there is no space inside the event horizon. In fact, If I understand correctly, the entity (”traveler”) to whom the event horizon catches up would experience traveling across the universe at the speed of light, as the event horizon became as big as the universe, since everyone always experiences their position as the exact center of the universe.
Mathematics has a very interesting role in theoretical physics.
Let me use as an example the Rydberg equation for calculating the electron energies for the hydrogen atom.
Rydberg observed the spectral lines of hydrogen and found an equation which predicted the various frequencies. This was found with no underlying theoretical basis for choosing the equation.
Many years later Niels Bohr supplied a theory which resulted in that same equation.
This raises the following question: "Does the lack of a theory render the mathematics INCORRECT?" Another question is: "Does the existence of a theory render the mathematics CORRECT?"
I would claim that the answer to both questions is: "No."
My rationale lies in the fact that it would appear that every equation describing the behavior of the physical world is simply an approximation based on various simpifications and assumptions.
For example, so-called "Newtonian physics" offers calculations which would allow one to predict the observed velocity of one object when viewed from the frame of reference of a second, moving object. Would such mathematical calculations be "correct"? The answer is that they are good enough for some circumstances and not for others.
Einstein developed a different mathematical expression for calculating relative velocities. His equation works just as well as Newton's but also is accurate for relative and observed velocities close to the speed of light.
Does this mean Newton's equations are WRONG and Einstein's equations are RIGHT?
The best answer to that question is that "It depends." For many circumstances, Newton is just as good as Einstein. When the day comes that we understand what "dark matter" really is, we just might find Einstein's equations as lacking then as we sometimes find Newton's lacking today.
The point I am trying to make is that it is just possible that mathematics NEVER describes any existing physical system exactly. But for some purposes, the math is really quite good. As for your original question, the Rydberg equation was probably able to predict the frequency of spectral lines that Rydberg was unable to observe.
That question wasn’t for you. I know all this! It was for the person on the thread denigrating math in theoretical physics.
You’re right. I mistook the context. My post was intended for thoughtomator.
May as well address this to both.
There is a qualitative difference in the way math is applied in physics today vs. in the past.
In the past, the applied math had real physical ties to reality.
With the relativity era that all changed. With relativity, one changes reality to match the math. It’s a fundamentally different process than the one used to derive equations from observation in the absence of underlying theory.
Today, the underlying theory is the starting point and observations are both altered and outright fabricated in order to make them match the theory.
Enter the math.
Math reduces the physical world to symbols. However, the symbol is only meaningful when used as an accurate proxy for the physical phenomena underlying it.
Today what we see is a systematic misuse of mathematical symbols in defiance of the physical realities. The presence of infinities, the abuse of time, requirements for extra dimensions, and so on and so forth.
To me, what is disrespectful of the impact of mathematics on astrophysics is not the challenging of the current paradigm, but its uncritical acceptance.
Throw in accelerating institutional corruption and peer review practices of increasingly poor quality, and a cutting edge consisting largely of claims derived from unrepeatable experiments, and what we have here is a false description of the universe on its final legs, as observations continue to blow irreparable holes in the model.
In the big picture, the fundamental problems are even higher level that that, though. The big picture problem is that our conception of the universe derives from an era before electricity. Which is kind of a big deal in terms of how the universe actually operates.
The mechanistic gravity-centric universe has failed just as completely as the geo-centric one. It is time for new conceptions that include from the start the new forces that we now know exist abundantly in creation.
You still haven’t answered a single question I have asked you?
You asked one question and it was answered, and in far greater detail than requested.
Is there something else you want or is this just a petulant reflex to realizing that one’s belief system rests on impossibilities?
.. That's irrelevant
Not knowing how the mechanism works..it independent of the observed effect ...
Are you contending gravity doesn't exist Just because we don't know how it works... I don't think so
Things are observed before we know how they work...
Our knowing how something works does not at that point bring it into existence....
So simple question: Has light been observed to be bent by gravitation effect... whether we understand the mechanism or not?
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