The groundbreaking American astrophysicist Vera Rubin, who shed new light on the movement of galaxies and proved that dark matter does exist, has passed away.
In our solar system, the planets obey theKepler's laws: the closer they are to the sun, the higher their speed. The planet Hema orbits the Sun faster than Venus and Earth, which in turn are faster than Mars, Jupiter, Saturn, and so on.
However, in the 70s it became clear that this was not the case everywhere. Observations of distant galaxies have revealed that stars at the edges of galaxies move faster than stars closer to the center. As far as we know, even in an entire galaxy, like in a single solar system, most of the mass is in the center and those closer to the center of mass should move faster.
The researchers' conclusion was that if the outer stars are indeed moving more, there is probably another mass at the edges of these galaxies that we cannot see, therefore they called this mass "dark matter". Behind the discovery was an extraordinary and groundbreaking scientist, who passed away this week.
Galaxies deviate from their path
Vera Cooper was born in Philadelphia in 1928. She was the second daughter of Philip Cooper, a Jewish electrical engineer born in Lithuania, and Rose (Appelbaum), a thinker at Bell Telephone Company. When she was ten, the family moved to Washington, DC. Vera was interested in astronomy from a young age, and her father supported and encouraged her. He took her to observations and lectures by amateur astronomers, and even helped her build her first telescope when she was 14.
Cooper studied for a bachelor's degree at Vassar College in New York State, one of the most prestigious women's colleges of its time. When she graduated in 1948, she asked to continue her studies at Princeton University, but was rejected because the prestigious university did not agree to accept women. She was eventually accepted to graduate school at Cornell University, and studied with some of the most prominent physicists of her time. There she also met Robert Rubin, a research student in physical chemistry, and they married a few months later.
In her master's thesis, Robin studied the movement of galaxies. Years earlier, the renowned physicist proved Edwin Hubble Because the universe is expanding, using measurements of the color change of distant galaxies. When a body is moving away from us at a very high speed, the wavelengths of its colors will seem longer to us, that is, they tend more towards the red tones, therefore the phenomenon is called "Redshift". Hubble looked at such measurements and discovered that the farther a galaxy is from us, the faster it moves away. The conclusion was that all galaxies started in roughly the same place, and that our universe is expanding and expanding.
Rubin delved into the data and discovered that many galaxies are not moving away from us directly, as expected from the expansion of the universe, but are also moving "sideways", that is, deviating from the path of rapid receding. The results of her research were not well received, and several leading journals refused to publish the article she wrote.
The mystery of dark matter
After her master's degree, Robin continued her doctorate at Georgetown University in Washington, under the guidance of George Gamow, from the progenitors of the big bang theory. She continued to study galaxies and their movement, and was among the first to realize that galaxies are not scattered in the universe in a random and more or less uniform way, but are concentrated in clusters. She finished her research in 1954, but even this work was not really recognized. It wasn't until the 70s, when more extensive research on extremely large cosmic bodies began, that Rubin's insights were accepted by the scientific community.
After receiving her doctorate, she continued to research at Georgetown University and teach there for another decade, advancing to the rank of professor. Her research dealt with galaxy movements, and among other things she began to delve into the issues of the rotation of various star systems around themselves.
In 1965 she moved to the Carnegie Institution in Washington, where she did her most famous research. She studied with her colleague Kent Ford the motion of the stars in the Andromeda galaxy, the Milky Way's small neighbor, in an attempt to understand the distribution of mass in the galaxy. To their surprise, it turned out that the movement of the stars in the outer part of the galaxy was at least as fast as the movement of the stars in its center.
Rubin and Ford examined the situation in a few dozen other galaxies, and concluded that this phenomenon is quite widespread. The apparent mass of the stars in the galaxy cannot explain the speed of the outer stars, so there is probably another mass that we cannot see. The idea of dark matter was raised as early as the 30s, but the work of Rubin and Ford provided the first evidence of its existence. Today, researchers estimate that 90-70 percent of the mass of the entire universe is dark matter. Many research institutions around the world are trying to decipher the nature of dark matter, including CERN, the giant European particle accelerator.
Asteroid and toilets
Rubin's groundbreaking work has earned her numerous scientific awards and honors, including the US National Medal of Science (1997), the Gruber Award (2002), and the Gold Medal of the British Royal Astronomical Society (1996). She also won an asteroid bearing her name, and in recent years she has been mentioned several times as a candidate for the Nobel Prize in Physics. "Dark matter has fundamentally changed our perception of the universe and revolutionized all of physics. The efforts to understand its nature occupy many researchers in astrophysics and particle physics," said Dr. Emily Levesque, an astrophysicist from the University of Washington In an interview with Astronomy magazine. "Alfred Nobel's will states that the prize in physics will be awarded for the most important discovery in the field. If dark matter doesn't fit this description, I don't know what does."
In addition to her groundbreaking scientific work, Robin also worked extensively to promote women in science, especially in astronomy. Among other things, she was the first woman to receive permission to operate the giant telescope at the Palomar Observatory in California, which for many years was the largest and most important telescope in the United States. One of her colleagues said that the observatories didn't even have women's restrooms, until Robin simply cut a woman's figure out of paper, stuck it on the door of the men's restroom in one of the observatories, and established a fact on the ground. Her activities for the advancement of women were also recognized, and in 1996 she was the second recipient of the Weizmann Prize, awarded by the Weizmann Institute of Science to leading scientists in the United States.
For many years, Robin combined her work with raising her four children. "Almost my entire career I worked as if I were part-time," she said in an interview with "Discover" magazine in 2002. "I left early to be with the children from three o'clock, and I did a large part of my work from home." She was successful on both fronts: her four children have doctorates in science - two of her sons are geologists, one a mathematician, and her daughter Judith followed in her footsteps and developed a career in the field of astronomy.
Robin continued to work at the Carnegie Institute until her retirement, and continued to be involved in scientific research until the last few years, when she was stricken with dementia, and could no longer work. She died on December 25 in a nursing home in Princeton, not far from the university that refused to accept her for studies only because she was a woman. "She was an accomplished scientist and a role model for young scientists," Carnegie President Matthew Scott paid tribute to her. "Vera Rubin was a national treasure".
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Miracles
Yehuda has already received a prize. the Ignoble Prize. He is nominated for another award.
Cheers p
I will explain again. A black hole in the center of the galaxy such as there is for example in the Milky Way is relatively tiny, a mass of several million suns SA which is not enough to change the conditions of an average galaxy that has a mass of about one hundred billion solar masses.. The mass required for the purpose of the correction is about a trillion suns, that is ten times the total mass in the galaxy. In addition, even if there is a black hole of this size in the center, it will only complicate the theory. It is true that the stars far from the center will rotate faster as required, but the inner ones will also rotate faster, so we have not solved the problem. There is a lack of mass in the galaxy far from the center and if you make it from a normal mass we will have a friction problem and the galaxy will not be able to rotate around an axis for billions of years.. But as you say, maybe small black holes that are scattered throughout the galaxy and around it, that will not cause friction (unless they collide with them?)... Maybe. But there is a study that was done that looked for the passage of such black holes against the background of the stars, light that would have passed by such a black hole would have been bent and this could be noticed. Unfortunately it was not diagnosed to the extent required.
Please respond gently
Sabdarmish Yehuda
(to Judah)
I was not convinced by your explanation which was somewhat vague.
I realized that cosmologists are very convinced that dark matter cannot play the role of dark matter, that it does not work out in the simulations.
Yehuda I don't know, I'll check on Wikipedia 🙂
to the opponent
Netanya is not in space??
What is it that there are thugs in space too?? How far did they go?! It's just unbelievable…
Cheers p.
Black holes are made of bully mass and we know how it will behave. And it does not match what we can demand from the dark matter. We can give the dark matter any property so that it does not interfere, for example it does not have the property of friction, because if it had this property it would interfere with the rotation of the galaxy. In addition, you can put it where you need it, for example, far from the center of the galaxy. Black holes are concentrated in the center of the galaxy and we require them to be also around the galaxy far from the center.. Also many studies that have been done prevent the possibility that black holes will have all the required effect of dark matter.
How much easier it is to give up gravitation at distances and look for another phenomenon that will allow the movement of galaxies..
Please respond gently
Sabdarmish Yehuda
yekumshut.freevar.com
To Judah
I have a fundamental, essential question here:
Black holes cannot be seen directly.
So what prevents me from asserting that there is no dark matter but only a mass of black holes - much more than people think? And that they are distributed in the galaxy according to the estimated distribution of dark matter?
They say there is more mass than "what we see". Who said that there is a direct and constant relationship between visible mass and the mass of black holes around? Maybe this ratio depends on the environment which is quite random?
The answer to this question will actually answer the presentation of the things I presented earlier.
Cheers p
After thinking, there is no difference if we start doing the calculations as you say - from the outside in instead of from the inside of the galaxy to the outside as usual. In both cases we will reach the same result - adding a lot of (dark) matter to the galaxy.
Sabdarmish Yehuda
Cheers P,
I'll think and answer you, usually you measure from the center outwards in the galaxy because up to a distance of a few thousand light years from the center everything goes according to Newton. Only later does the deviation become apparent. You are trying to give an idea of the outside in. interesting.
Yehuda
to Judah
The outer stars move at a given speed, from which the mass of the galaxy must be derived. (This essay is embodied in stars and black guys).
Once the mass of the galaxy is known, the (tangential) velocity of stars that are more inner must be calculated. Then, from their tangential velocity, derive the intrinsic mass as a function of distance from the galactic center. In this way it will be possible to calculate the distribution of matter within a galaxy.
For example. Assume the external tangential velocity (distance 100 units from the center) is 100% (250 meters per second).
Suppose the tangential velocity at 80% distance from the center is V, then:
If the value V is high, say 90%, then the internal mass inside the sphere whose radius is 80% is high.
And if the value V is low, say 70%, then the internal mass of that ball of 80% is low.
After calculating the mass of the spheres at 90%, 80%, 70%, 60% and so on, we will have an idea of the mass density in the galaxy as a function of distance from the center. We can also measure the ratio between the brightness and the mass, and associate the anomalies with black holes.
I am not a professional physicist. i wish i was I would love to get to the bottom of things.
Chaim P
My explanation refers to dark matter and not dark energy. I will explain again. The rotation speed of the spiral galaxy in its outer layers is greater relative to what results from the visible mass in the galaxy. About 250 km per second instead of 70 km per second according to Newton. If you want to continue to hold to Newton's formula, you have to add dark matter to the galaxy, but in the outer layers of the galaxy. Because if they put the material inside, what will happen is that the inner parts of the galaxy will also move faster.
I hope I understood.
Happy New Year!
Sabdarmish Yehuda
yekumshut.freevar.com
Chaim P
You mean maybe Mordechai Milgrom.
I didn't understand how your comment was relevant.
My explanation refers to dark matter, and you refer to dark energy, which is active on an intergalactic level.
My explanation pretends to argue that there is no need for dark matter.
In any case, I know that in computer simulations, it turned out that dark matter must be "implanted" in order for the findings to correspond to Newton.
That is, that my explanation probably does not answer all the problems.
I know of an Israeli scientist (whom I don't know what happened to him) who also went in your direction: a correction in one of Newton's formulas. (I heard about him about 7 years ago).
Cheers p.
The gas clouds that are outside the galaxy at distances of tens of thousands of light years outside it, are still moving at high speed and do not show a "will" to reduce their speed according to Newton, therefore it is necessary to add a dark mass greater than the baryonic mass of the galaxy around the galaxy and outside it in order to maintain Newton's formula . Sorry, your idea doesn't pass the measurement test.
Sabdarmish Yehuda
Fix:
Pen error. Should be: our sun orbits the center of the galaxy at high speed with another sun that is further inside. And **slower** is used differently which is more external.
Speculation on the tangential velocity within a galaxy.
A tunnel will be cut from the surface of the earth through the center of the sphere to the other side.
If we check inside the tunnel the force of attraction to the center of the ball, we will find that it is impossible to use Newton's formula as it is. As we move towards the center of the ball - the mass that pulls us in will decrease, and the mass that pulls us back will increase. The acceleration g will decrease until it is zero at the center of the ball.
Various considerations lead me to think that the acceleration g is proportional to r which is the distance from the center of the ball.
I'm sure these calculations are quite similar to calculations on a galactic level. If a body is inside a galaxy, the attraction to the center diminishes and increases the closer the body is to the center of the galaxy (not to be confused with attraction to gravitational points such as black holes). This means that the galactic gravitational acceleration is getting smaller.
And it also means that the inner stars move more slowly than the outer stars, in their orbit around the galaxy.
For example: our sun orbits the center of the galaxy at high speed while another sun is further inside. And faster is used differently which is more external.
Why doesn't this happen in the solar system? Because 99% of the mass of the solar system is the sun itself.
(Of course, a body that is outside the galaxy will behave normally and will be disciplined by Newton's laws).
I am not as sensitive as Yehuda'la and you are welcome to tear my speculation to pieces.
I forgot to explain why - the reason is that visible light is swallowed by interstellar gas and dust before it reaches us, while infrared light is almost never swallowed.
A picture is beginning to emerge that dark matter is the result of a measurement error. It turns out that in visible light the masses in galaxies are not measured correctly. Infrared light is much more accurate. So when measuring in infrared light it turns out that in the outer part of 153 measured galaxies there is a complete match between the Newtonian/Einsteinian calculation and the rotation speed of the stars in the galaxy. In the inner part there is still a deviation, 2 times (and not 5 times as assumed by dark matter researchers). This deviation may also be corrected in the future. In any case, such a small deviation is not a "smoking gun" for dark matter.
See:
https://arxiv.org/abs/1609.05917
You need to click on "Download PDF" and look mainly at drawing 3.
Yehuda
If someone on the committee knew this - why didn't they publish any article on the subject?
Dark matter is currently nothing more than a theoretical entity that tries to explain the movement of galaxies. So far there is no proof of its existence. Another explanation could be related to what Sabdarmish Yehuda suggested that there is indeed a difficulty in the equations we use. There may be other theoretical explanations that would settle the anomaly in the movement of the galaxies.
Well, really, miracles, the Nobel Prize Committee will award a prize for something it always knew?
Yehuda
If the members of the Nobel Prize committee are so smart - why don't they give you the prize? I'm asking seriously.
No one has yet received a Nobel Prize for dark matter. They are smart enough there to understand there that its existence is very doubtful. When the data measured in the galaxies do not match in a tremendous way what is obtained from Newton's formula, the formula and not the data should be boldly thrown away. Always when there is a massive mismatch, the formula must be thrown away and this is for every formula. This is not a small correction like the one that led to the discovery of the planets Uranus, Neptune and Pluto. In the galaxies this is a huge deviation! But, make Newton's formula and/or Kepler's laws sacred, they are not touched, while the well-measured data, you change as much as you want, the main thing is to fit the holy formula. And the dark matter is added massively, even adding sometimes tens and hundreds of times the measured baryonic matter, and when it is still not enough, they add another "invention of the century" - the dark energy.
Vera Rubin was a smart scientist but here she was wrong, and made one of the most radical scientific mistakes of the twentieth century.
Please respond gently.
A good civil year for everyone
Sabdarmish Yehuda
yekumshut.freevar.com