This is what Nobel laureate Professor Robert Kirchner said at the annual conference of the Israel Physics Society held at the Technion. Egocentric thinking
"When politicians talk about science, they talk about its products: a strong economy, national resilience and advanced medicine. In other words, they talk about wealth, security and immortality. But scientists wouldn't be doing science if it was all boring. That's why it's important to me to show that science, and astrophysics within it, is fascinating and brings great pleasure to those involved in it."
These words were said yesterday at the beginning of the week at the Technion by Professor Robert Kirchner from Harvard University, at the opening of the 57th annual conference of the Israel Physics Society. The conference was concluded by the lecture of the winner of the Nobel Prize in Chemistry for 2011, Professor Danny Shechtman from the Faculty of Materials Engineering at the Technion.
Professor Kirchner lectured on the dynamics of the expansion of the universe. Initially, scientists believed that the boundaries of the "Milky Way" were the boundaries of the universe. With the improvement in telescopes it became clear that the "Milky Way" is one of many galaxies. He described the work of Albert Einstein, who coined the "cosmological constant" in 1917, and assumes the existence of a static universe - a universe that neither expands nor contracts.
Edwin Hubble, after whom the Hubble Space Telescope is now named, disproved a few years later these two assumptions - that the universe is static, and that the Milky Way and the universe are one. Hubble stated that the relative paleness of an observed galaxy, or its dimness, is evidence that it is further away from us. In addition, he noticed that the frequency of the radiation emitted from it is shifted and the deviation increases the farther away the galaxy that emits it is. A change in frequency can be caused by movement, the Doppler effect (similar to the change in the siren sound of an ambulance approaching and moving away). Observations conducted over decades, based on this determination, proved that the galaxies are moving further and further "outwards". From this they concluded that the universe started from one small point in a huge explosion, the "Big Bang". Recently it became clear that the universe is expanding at an accelerated rate. The Nobel Prize in Physics was awarded this year (2011) to three scientists who proved this (some of whom were former students of Prof. Kirchner). To explain this acceleration, the existence of an energy called "dark energy" must be assumed.
The big bang happened about 14 billion years ago, and since then the universe has not stopped expanding. However, in the first nine billion years, the expansion of the universe was constantly slowed by the gravitational force of matter and the resulting attraction between galaxies; Only about five billion years ago, with the galaxies moving away from each other, when the power of dark energy overcame the force of gravity, the expansion of the universe began to accelerate.
"Humanity is egocentric, so it has never stopped striving for an egocentric universe," said Kirchner. "Once every person thought he was the center of the universe. Then humanity thought that the earth was the center of the universe and the sun revolved around it. Then she realized that the earth revolves around the sun, but had a hard time understanding that the sun is not the center of the universe.
It is a mistake to think that today we are exempt from this egocentricity, because even when we imagine the expansion of the universe, we imagine it as if the universe is expanding from us and beyond, and this is a big mistake that stems from that egocentric thinking. In fact, everyone is distancing themselves from everyone else."
"So now we know that the universe is expanding, and that the expansion is accelerating. To explain this and other findings we must assume that the composition of the universe is: 73% of it is dark energy, 23% - dark matter (matter that we cannot see but conclude that it must exist) and only 4% - atoms, meaning matter as we know it. But we don't really know what dark matter and dark energy are. And maybe we're wrong and actually don't understand how gravity works?"
370 participants took part in the gathering, some of them from abroad. The chairman of the conference was Professor Ilan Rees from the Faculty of Physics at the Technion
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And seriously, I just found an important discussion about gravity loss
http://www.facebook.com/group.php?gid=24455461228#!/group.php?gid=24455461228&v=wall
: )
I just received an important supplement in e-mail that sharpens the taste:
Lecturer in one of the lectures: "During the emission of the sperm in the man, the sperms move inside a shell of sugars that protects them."
Immediately one of the students raises her hand and asks: "Wait, then why does it still taste bitter?!"
Silence among those present, and the student turns very red...
The lecturer answers her: because the sweet taste is only felt at the tip of the tongue.
So she became even redder and leaves the class...
Happy new year
And completed a signature, civil as above, good
If we've already started with university jokes, then here's the one I like the most:
http://www.youtube.com/watch?v=UTby_e4-Rhg&feature=youtube_gdata_player
These jokes are very old, but always funny again 🙂
Here are some more:
"Now we will move all the Aryans to one side, and we will get the final solution"
(a mechanics lecturer solves an equation with the letter R, the Hebrew University)
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Lecturer: Suppose I have three balls in the jar, and I want to choose one...
Electrical Engineering Assistant: We are not math students. Can you give us an example related to the field we study?
Lecturer: Yes. Let's say I have three resistors in a jar and I want to choose one...
(An introductory course to probability for electrical engineering students: Technion, 1999)
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A student went to open the window. The lecturer: "No no! It will be fine, don't jump!”
(Faculty of Mathematics, Technion.)
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Student: "Wait, is this sentence correct?"
Lecturer: "No... do you want a longer answer?"
Student: "Yes"
Lecturer: "Nooooo"
(numerical systems, software engineering, Ben Gurion University)
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"I have a pipe and you (pointing to a student) have another, bigger pipe
How can we compare the performance of our pipes?"
'Lecturer in flow tries to clarify the Reynolds number'
. . . after a while . . The lecturer explains about air density:
The lecturer: "Now that I'm waving my hand, you don't feel it, but...
…suppose you were with me (pointing to a student) in a jelly bath then you would feel the movement!”
Student: "I don't want to compare pipes with you and I don't want to be in a jelly bath with you"
(Flow course, biotechnology engineering, Ben Gurion University)
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Student: "Can you give an example of a function that is a derivative once, but not twice?"
Lecturer: "Yes. I can." *continues the lesson*
(Infi, Tel Aviv University, Faculty of Exact Sciences, Physics)
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"Gauss is the prince of mathematics..."
Student: "So who is the king?"
The lecturer: "What do you mean? Elvis!”
(Lecturer for Hadoa, in the introduction to Gauss law, Technion)
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"Another parameter is needed, because we are not in biology"
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A programmer goes shopping. His wife tells him: Bring bread, and if there are eggs, bring 6. He returned with 6 loaves of bread.
His wife asked what happened, he answered her: there were eggs
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Michael, if it was possible to give a like to the comments, you would get it.
Very entertaining 🙂
I just received the following group by email.
I decided to share it here because the fourth story concerns the use we have always made of gravity.
Lecturer in one of the lectures: "During the emission of the sperm in the man, the sperms move inside a shell of sugars that protects them."
Immediately one of the students raises her hand and asks: "Wait, then why does it still taste bitter?!"
Silence among those present, and the student turns very red...
(The Technion, Biology)
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Student: "There are transformers that hum when they work. Why ?"
Lecturer: "You would also be humming if you had 50 cycles per second..."
(Ben Gurion University, Department of Electrical and Computer Engineering, Introduction to Electrical Engineering 1)
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"... 15-20 minutes, and I'm done. Without going up and down..."
(Lecturer of organic chemistry, explains why it is better to give up the break and continue the lesson in sequence).
(The Hebrew University )
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The lecturer: "Really, I once did this experiment with my son!
I sat him on a swing and explained to him about the forces acting on him...
So he said to me: Father, what are you stupid? Swing and that's it!"
(Technion, classical physics)
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Lecturer: "I don't understand what you are saying. You must be a relative of my wife's…”
(Technion Preparatory School)
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The lecturer: "You can pass the test, ask those who took it the previous semester."
Student: "You can ask them now. Most of them are here..."
(Ben Gurion University, Department of Economics)
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Student: "May I have time to copy?"
Lecturer: "Yes, take advantage of the time I erase the board."
(The Technion)
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Before the test, the lecturer is asked about the test and he answers: "You will not have any surprises in the test!"
In the test no one understands anything, very difficult and unclear questions.
Students come to the lecturer with complaints: "Did you say there would be no surprises in the test?!"
Lecturer: "That's right. You too, as in all years, will have 70% failures..."
(Ben Gurion University, engineering, C programming)
*****************************
Lecturer: "I can play Tetris with you:
Anyone who disturbs will move to the last row and when the last row is full it will fly out."
(Tel Aviv University, exact sciences)
*****************************
"I'm asking you... at the end of the semester there is feedback from lecturers, give me 2, I can no longer pass this course."
(The Technion, Physics 2m)
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Lecturer: "If a projectile is fired towards the sun, its speed will increase during movement"
Student: "..but the lecturer, the bullet will melt long before..."
Lecturer: "So we shot him at night..."
(Hebrew University, Private Mechanics and Relativity, 2006)
******************************
(first lesson)
Lecturer: "I'm glad you understand. Soon it will change…”
(Tel Aviv University, Infi)
*******************************
Before a notorious test on computers, one of the students asks: "What reference material should you bring to the test?"
Practitioner: "I think it's best for you to bring Psalms..."
(Ben Gurion University, Electrical and Computer Engineering)
*******************************
(alarm siren sounds)
Lecturer: "If you all burn to death, you don't need to submit assignment 12..."
(Open University, film course)
*******************************
"The attitude of physicists to mathematics is like the attitude of criminals to a rulebook. You should know, and you should know how to get around."
(Tel Aviv University, Memphis)
********************************
Lecturer: "Now we will open the Newton binomial according to Taylor's column."
Student: "It's like saying son of a bitch and your mother's cup in one curse..."
(Tel Aviv University, Mechanical Engineering, Infi 1)
******************************
The lecturer presents an American question from a previous test on the board.
Lecturer: "Who thinks the answer is A?"
How many students vote.
Lecturer: "Who thinks the answer is B?"
Some other students vote.
Lecturer: "Who thinks the answer is C?"
A few more students vote.
Lecturer: "Who thinks the answer is D?"
Some students vote as well.
Lecturer: "You see? That's the problem with democracy, letting people decide on issues they don't understand anything about!"
(Tel Aviv University, Discrete Mathematics, Faculty of Exact Sciences, Semester 2004)
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In addition, it is worth noting the following fact:
The fact that we understand well the strong, weak or electromagnetic force is a result, in part, of the fact that we did not try to explain them as mistakes in understanding gravity.
Yael:
Gravity was discovered long before all other forces.
We also harnessed it for our needs many years before we even started to come close to understanding it and we always knew that if we used a catapult to throw a stone beyond the walls of the fort it would eventually fall and we could direct it so that it would fall inside the fort.
The fact that they did not find a graviton does not mean much and the theory of relativity is not at all based on any elementary particles - neither the graviton nor the Higgs.
Anyone who wants to attribute the expansion of the universe to a problem in understanding gravitation - shame on him - but he can equally attribute it to a problem in understanding the strong force.
Of course he can also attribute it (and more logically) to another mechanism - beyond all known forces.
Michael,
Thanks for the idea. I will look there too 🙂
Also in my personal opinion it is jarring to treat things that work well as if they are wrong. But sometimes the least likely assumptions turn out to be correct and that's why it makes sense to re-examine things.
The amount of sensors at CERN eclipses anything that came before. By the way, Israeli companies and Israeli universities have a large part in building sensors in general and in particular the most extreme Atlas sensor.
Of course I saw my father!
The point is that they predict that the Higgs is expected to emerge at about 120GEV while the Tevatron achieved 512GEV already in 1983 (about 30 years ago), so apparently the Higgs should have been found a long time ago. At CERN they hope that because they collect more data and the appearance of the Higgs is rare, so maybe the Tevatron missed it...
Yael, you probably missed this news
https://www.hayadan.org.il/higgs-boson-maby-found-1312118/
Mr. Michael,
You certainly asked legitimate questions. The point is that there are other legitimate questions that as of today we do not have answers to. Sometimes even the observations contradict the teachings we have:
http://en.wikipedia.org/wiki/Unsolved_problems_in_physics
All three other forces are well known to us: we know how to explain them, measure them, prove them and even harness them for our needs. We know very, very little about gravity. Based on the accepted theories, it was thought that gravity would be explained in the Tevatron accelerator, the accelerator has reached the end of its life and has already been shut down and gravity has not yet been discovered. Two years already looking for the explanation in the LHC and practically nothing. According to the existing teachings, the particle should have emerged under the conditions that humanity has had for many years - this is not happening. Why isn't this happening?
jubilee:
I didn't claim you had a problem with gravitation.
I referred to Yael's attempt to present claims that do not create any problems for gravity as problems of gravity and to the fact that you did not point out that these are not problems.
In relation to the accelerated expansion of the universe - every force creates acceleration so that if there is a force driving the expansion - it will necessarily be accelerated.
We currently do not know the reason for the existence of this power and it is okay to try to find out.
However - it seems a little strange to me to look for the reason precisely as an error in things that work instead of something new.
Why does the existence of the electromagnetic force or the strong force or the weak force not make you look for its cause as an error in the theory of relativity?
Michael,
I have no problem with gravity in my daily life and also in many local and even quite distant observations (recently I also lost a lot of my body weight 🙂 ).
I have a problem with the accelerated receding of the galaxies.
A few weeks ago I proposed here a model of reverse gravitation that is only noticeable at orders of magnitude of intergalactic distances. I offered all kinds of hypothetical models that it would be a shame to tread on them again. As long as there is no better explanation for the phenomenon, I allow myself to have fun with them.
Yuval, Yael:
I don't understand the attempt to point with the unconfirmed speculation of the fifth force to some problem with gravity which is confirmed every moment of our lives.
It is very easy to imagine mechanisms that produce both repulsion and attraction.
I assume that any of the readers here can think of a spring that repels when compressed and attracts when stretched (and oscillates around the equilibrium point when left to its own devices).
There are also mechanisms that create forces that repel certain bodies and attract others (electromagnetic fields).
Yael,
Intuitively, we only know the attraction aspect of gravity and that is why "gravity" is accepted by us as a synonym for "gravity". But physics is not satisfied with intuition. It is possible that the "fifth force" is nothing but the repulsive aspect of gravity.
Mr. Yuval Chaikin,
I don't understand your thinking, how can gravity be a "repulsive force"?
Are you ready to elaborate? It's quite clear that you have something more extensive in mind...
Thank you Yael,
Do you think gravity, like the electromagnetic force, also has an aspect of repulsion? If so, this could explain the phenomenon that was named "dark energy".
http://en.wikipedia.org/wiki/Fifth_force
Yael,
Can I please have a link to "The Fifth Force"? What I found on Google about it does not belong to physics.
Professor Kirchner is euphoric that he assumes there is gravitation at all...
The curious reader is invited to read about the "fifth force" and learn the basis of the concept
of 4 forces is not certain.
: )
Thanks, Michael 🙂
A. Ben Ner, my opinion is the same as yours.
It also occurred to me that the Nobel Prize might not grow between the pages of "Hidan", but there is excellent fertilizer for the growth of politicians.
The key sentence in the article (in my opinion) is:
"...and maybe we're wrong and actually don't understand how gravity works?..."
Admit it, when Kirchner says it, it sounds a little different than Sebdarmish says it...
but…….
Who knows what other discoveries have been made to science? extremely intriguing.
Yuval (yes Chaikin):
You can add at least one more to the number 🙂
jubilee! To avoid unnecessary confusion, please specify that you are not me.
who knows? Maybe someone will pay attention 🙂
In any case, your response shows that at least one person read my words, and I'm certainly satisfied with that.
Thanks
If you know he doesn't read comments, why are you contacting him?
Professor Kirchner,
If you had read comments in "Hidan", you would have seen that the questions you are talking about have already been resolved a long time ago.
Your claim about the orientation of politicians who talk about science is perhaps true in most of the world. But in Israel, when politicians talk about science, they never cease to squint at the ultra-Orthodox voice, the voice of the community that has long since solved all the riddles of the universe and is diligent about conveying its message everywhere - even above the comment stage here at "Hidan".
🙁