Is Renate Loll's Approach to Quantum Gravity the Key to Unifying Physics?

[marcus]

Erik Hardeman recently did an article about Renate Loll in the Utrecht U. newspaper. Timbuqtu (a Dutch student at Utrecht) kindly translatated some short passages in the "Quantum Graffiti" thread.
I have tried systrans at Babelfish on the whole article, which is long. I will see if there are some more exerpts that might be worth keeping---and editing to make the English sound more sensible. what follows is partly by Timbuqtu and partly by Babelfish and me.

####$#scratchpad$######$# Renate Loll (43) has been working in Utrecht for four years now. She has become an eminent scientist and an enthousiastic advocate for more women in science. She received three million euro from Brussels for a Europian network and also a vici-prize of 1.25 million euro last year. Enough money to keep searching for the holy grail in physics. A vacuum which is nevertheless not empty; a space time consisting of bits of foam; and our three-dimensional universe that is actually four-dimensional. The reality that Renate Loll studies is full of paradoxes and contradictions. In her work-room at the Minnaertgebouw, the German woman cleared up her interviewer's misconceptions. "It is not easy explain what implies my research. To put it briefly, I search for the structure of spacetime, but to be able to understand what I mean by that, you must first of all depart from the common sense idea that we live in a space of three dimensions, in which a clock tells the same time for everyone. For our daily life is that a very useful assumption, but just one hundred years ago, with his relativiteitstheorie, Einstein made clear that fundamentally no sharp distinction exists between space and time. What one person sees as a bit of time, could for another be a bit of space. In fact according to Einstein we live in a four-dimensional reality: spacetime. [paragraph header quote: 'You must depart from the common sense idea that we live in a space of three dimensions, in which a clock tells the same time for everyone.'] Now we couple that with an imaginary microscope which examines space time. You would expect that on a very small scale in the space time, below that of our well-known particles, there is no more matter present. Between those elementary particles then therefore absolute vacuum would dominate. But the quantumtheorie, which was developed in the 1920s, says that at this very small scale what happens is a completely different story. According to that theory the vacuum is in reality an extended sea, where particles constantly arise and vanish. Those quantumfluctuations take place on scales which are still millions of times smaller than the scale of quarks (10 to the minus 19 meters), the smallest well-known elementary particles. We still have no precise idea how this happens, but it seems that, on the Planck scale of 10 to the minus 35 meters, spacetime itself starts to deform. It not simple will be there experimental come. Our particle accelerators will never be able to show us what takes place at this very small scale and the relativiteitstheorie does not make predictions concerning events at that scale. In fact it's a major unresolved paradox in modern physics that we have two different theories, both describing a part of physical reality in an extremely elegant manner. But they have been based on such different premises that they are total incompatible. For many years already, theorists have searched for the Holy Grail of physics, the theory of quantum gravity (also: quantumgravitatie), which will resolve this paradox by bringing the behavior of the largescale structure of the cosmos (explained by the relativiteitstheorie) and that of the smallest particles (explained by the quantumtheorie) together in one equation. Among physicists there is widespread agreement that the key to such a theory lies in an adequate description of the structure of the space time, but the solution is sought in several directions. Many colleagues of Renate Loll think that superstring theory holds the most promise for reconciling the relativiteitstheorie with the quantumtheorie, but she herself sees more merit in an approach which does not require assuming extra dimensions. "I try a model essay that at the quantum scale as well as at a larger scale provides a realistic description of the structure of the space time. Now at the smallest scale, such high energy fluctuations are involved that spacetime there is probably bent to a great extent. But that is only conceivable if we assume that it is extremely deformed or else broken up into uncountably many flecks of quantum foam. The large problem is however that there is no theory that can explain how the sum of all those microscopic small scrap pieces of quantum foam produce a beautiful continuous four-dimensional reality in the macro world. All attempts to construct such a theory have so are gotten stranded. Sometimes that sum produced a two-dimensional world, then a world came with infinitely many dimensions." [paragraph header quote: 'I can remind myself still well how it felt then we that outcome saw appearing. That was a magical moment'] There were yeas of struggle until I first got the idea that what many theorists had lost sight of was the need to include causality---cause and effect---in the picture at very small scale. So I put that in as an absolute requirement in my calculations. then I worked for several years with a Danish and a Polish colleague to work out the consequences of that idea. And it succeeded, because in an article last year we showed that a realistic four-dimensional universe does indeed arise, under the condition of causality, from miniscule bits of four-dimensional quantum-foam. I can still remember vividly how it felt when we saw that that outcome appearing. It was a magical moment." The article by Loll and her colleagues was received worldwide as a breakthrough on the way towards a better grasp of the structure of spacetime. It is still a question in many people's minds whether it offers insight into the long-awaited theory of quantum gravity. It is clear however, that the leadership at the Spinoza Institute made a good bargain, with this appointment. Why did a German scientist swap an appointment at one of the renowned Max Planck Institutes in her native country for a position as senior lecturer in Utrecht? Loll: "Initially I came to Utrecht because I could get a permanent appointment and possibly later become a professor. But I certainly also chose Utrecht because of the reputation of this institute and because of Gerard 't Hooft. Not that I closely cooperate with him, for Gerard doesn't work together with anyone. His remarkable power is his totally individual stand alone way of thinking. He's very critical and we of course don't always agree on the problem of quantum gravity, but what I find very special about him is that he does not only attend colloquia and seminars, but he also visits talks by master students and he participates in their discussions. You name me another Nobel laureate who does such things. Gerard is really a part of the spirit of the place, which makes it extra encouraging to work here."[paragraph header quote: 'This is not the only place in the world where it is assumed girls won't do well in exact sciences. What's worse, I think, is that people don't even acknowledge there's a problem.'] Renate Loll turned out to be in the four years since its appointment in Utrecht itself not only as an eminent scientist, but also as an enthusiastic lawsuit deliveryman for more women in science. The position of women lies me after to the heart. In the bètahoek I find the situation in the Netherlands without more shocking. In Germany is free the matter already touched, but here is it still more terrible. The idea is not only here almost absent that little girls could be sometimes well in exact sciences. Still more terrible I find that even the notion is lacking that there is talk of a problem. My male colleagues are me very dear, and it is also not this way that they are against women, but they have no idea how male the system in which they, is function and hoezeer that disadvantages many women. If coordinator of the Enrage (European Network or Random Geometries) - network of the European Union Renate Loll have meanwhile found a way to give steuntje in the back to female scientists, she tells. It concerns a network of scientists who in several areas the same type uses geometrical techniques such as I do in my study into quantumgravitatie. One of the objectives of that network is the participation of women in exact science promote. You can think differing concerning Europe, but the European Union have a very lighted idea concerning women in science. One is in Brussels more progressive than in which of the Member States also. In all European programmes attention applies to the position of women expressly as a criterion. But did you think that one what there attracted itself? Generally it means that in a research proposal of sixty pages somewhere in the back of state: by the way, we have who also someone pays attention to the women in our network. Total ridiculous. In my network have I that more tries incorporate. Of the thirteen groups in Enrage is there three, in which excellent women play a prominent role. All three I extra for a promovendus have given. Also itself Renate Loll have had overcome the necessary obstakels. I was the kind of little girl that is already taking apart radios to see how they worked, but I have long sit reflect what I would will do on the university. Then I thought: why do not start you with physics, which is possible never angry. My parents found it very well, but further I have got little support of my surroundings, not only during my study, but also afterwards. I as a woman really have had fight to save it in science. That I didn't get a steady job until I was 39, speaks volumes. Superstring theory According to superstring theory, the most elementary particles in the universe are not points, but a kind of trembling elastiekjes, of which the ultrasounds occur to our as particles, such as electrons and photons. Although the theory seemed initially a promising candidate the antagonism between relativiteitstheorie and quantumtheorie, becomes always more clear bridge that she ensures for its part new problems. The most serious complication is that according to this theory our world --- without we see something of it in daily life --- belongs to a universe of ten or more dimensions. Perhaps our three-dimensional universe floats in higher dimension surroundings - in the same way that a flying moquette of two dimensions floats in three-dimensional space ---- separated from a shadow world, which might be only a few tenths of a millimeter distant from ours, as Spinozawinnaar Robert Dijkgraaf vividly described it not long ago. The solution for this problem will probably come from a totally unexpected direction. Although Renate Loll is carefull to put it circumspectly, so as not to offend any of her colleagues, it is clear that she does not see much bread in research in this direction. "At the beginning, superstring theory looked simple, and as a result, very attractive, but gradually complications have more and more appeared, as a result of which I now find it a rather far-fetched theory. Moreover is very unclear if the string approach will lead somewhere. For this reason I prefer my own treatment." Those have, moreover, already produced concrete results. Just like Renate Loll also Nobel Prize winner Gerard t Hooft has not been persuaded of the correctness of string theory. But whether the approach of his Utrecht colleague is correct, remains for him an open question. "Renate clearly made progress last year, but she is still not there by a long ways. It is even the question if she is on the right track, as concerns quantum gravity. Although I myself am exploring a different solution in the direction of quantum gravity, I find that superstring theory at this moment still holds the best cards in hand. We have meanwhile encountered a number of annoying obstacles, but nevertheless that treatment [stringtheory] is still concrete and more structured than other attempts to reconcile the relativiteitstheorie and the quantumtheorie with each other. This does not means that Renate cannot it at the straight end. My philosophy is: let everyone muddle on. She must especially continue with where she is busy, because the solution for this problem probably comes along from a completely unexpected direction.. Erik Hardeman Appeared on 13-10-2005 in Ublad 7 (37).$#############

My comment. Note the favorable words about string theory from Gerard 't Hooft near the end. he seems to be saying to try every approach that has a reasonable chance.

 

[marcus]

the original is here:
http://www.ublad.uu.nl/WebObjects/UOL.woa/4/wa/Ublad?id=1022717

anybody who can and wants to help improve the translation, please do.

Eventually I'll figure out what exerpts of this to add to the Quantum Graffiti thread here:
https://www.physicsforums.com/showthread.php?p=796105#post796105

Here is the systran translator I used:
http://www.systransoft.com/index.html

I haven't had much experience with online machine translation, beyond this Dutch to English example. Let us know if you have a differernt favorite.

 

[marcus]

Second draft of Hardeman interview with Loll

Here is a second draft of the Hardeman profile of Renate Loll, published in the Ublad of 13 October 2005.
http://www.ublad.uu.nl/WebObjects/UOL.woa/4/wa/Ublad?id=1022717
The Dutch original has been, in a certain sense, translated (thanks to Babelfish and the Utrecht physics Masters student Timbuqtu)
####$#scratchpad$#########

Renate Loll (43) has been working in Utrecht for four years now. She has become an eminent scientist and an enthusiastic advocate for more women in science. She received three million euro from Brussels for a Europian network and also a vici-prize of 1.25 million euro last year. Enough money to keep searching for the holy grail in physics.

A vacuum which is nevertheless not empty; a space time consisting of bits of foam; and our three-dimensional universe that is actually four-dimensional. The reality that Renate Loll studies is full of paradoxes and contradictions. In her work-room at the Minnaertgebouw, the German woman cleared up her interviewer's misconceptions.

"It is not easy explain what's involved in my research. To put it briefly, I search for the structure of spacetime, but to be able to understand what I mean by that, you must first of all let go of the common sense idea that we live in a space of three dimensions, in which a clock tells the same time for everyone. For our daily life, that's a very useful assumption, but just one hundred years ago, with his relativiteitstheorie, Einstein made clear that fundamentally no sharp distinction exists between space and time. What one person sees as an interval of time, could for another be one of space. In fact according to Einstein we live in a four-dimensional reality: spacetime.

'You must let go of the common sense idea that we live in a space of three dimensions, in which a clock tells the same time for everyone.'

Now we couple that with an imaginary microscope which examines space time. You might expect that on a very small scale, below that of our well-known particles, there is no more matter present there. Between those elementary particles, therefore, an absolute vacuum would prevail. But the quantumtheorie, which was developed in the 1920s, says that at this very small scale what happens is a completely different story. According to that theory the vacuum is in reality an extended sea, where particles constantly arise and vanish.

Those quantumfluctuations take place on scales which are still millions of times smaller than the scale of quarks (10 to the minus 19 meters), which are the smallest well-known elementary particles. We still have no precise idea how this happens, but it seems that, on the Planck scale of 10 to the minus 35 meters, spacetime itself starts to deform. It's not simple to observe experimentally. Our particle accelerators will never be able to show us what takes place at this very small scale and the relativiteitstheorie does not make predictions concerning events at that scale.

In fact it's a major unresolved paradox in modern physics that we have two different theories, both describing a part of physical reality in an extremely elegant manner. But they have been based on such different premises that they are total incompatible. For many years already, theorists have searched for the Holy Grail of physics, the theory of quantum gravity (also: quantumgravitatie), which will resolve this paradox by bringing the behavior of the largescale structure of the cosmos (explained by the relativiteitstheorie) and that of the smallest particles (explained by the quantumtheorie) together in one equation."

Among physicists there is widespread agreement that the key to such a theory lies in an adequate description of the structure of the space time, but the solution is sought in several directions. Many colleagues of Renate Loll think that superstring theory holds the most promise for reconciling the relativiteitstheorie with the quantumtheorie, but she herself sees more merit in an approach which does not require assuming extra dimensions.

"The model I'm working with attempts to provide a realistic description of the structure of space time both at the quantum scale and at larger scale as well. Now at the smallest scale, such high energy fluctuations are involved that spacetime there is probably bent to a great extent. But that is only conceivable if we assume that it is extremely deformed, or else broken up into uncountably many flecks of quantum foam. The big problem, however, is that there is no theory explaining how the sum of all those microscopic small scrap pieces of quantum foam produces a beautiful continuous four-dimensional reality in the macro world. So far, all attempts to construct such a theory have have gotten stranded. Sometimes that sum produced a two-dimensional world, and sometimes a world with infinitely many dimensions."

'I still remember vividly how it felt when we saw that that outcome appearing. It was a magical moment'

It took years of struggling with this, before I first got the idea that what many theorists had lost sight of was the need to include causality---cause and effect---in the picture at very small scale. So I put that in as an absolute requirement in my calculations. Then I worked for several years with a Danish and a Polish colleague to discover the consequences of that idea.

And it succeeded, because in an article last year we showed that a realistic four-dimensional universe does indeed arise, under the condition of causality, from miniscule bits of four-dimensional quantum-foam.
I still remember vividly how it felt when we saw that that outcome appearing. It was a magical moment."

The article by Loll and her colleagues was received worldwide as a breakthrough on the way towards a better grasp of the structure of spacetime. It is still a question in many people's minds whether it offers insight into the long-awaited theory of quantum gravity. It is clear however, that the leadership at the Spinoza Institute made a good bargain, with this appointment.

Why did a German scientist swap an appointment at one of the renowned Max Planck Institutes in her native country for a position as senior lecturer in Utrecht?

Loll: "Initially I came to Utrecht because I could get a permanent appointment and possibly later become a professor. But I certainly also chose Utrecht because of the reputation of this institute and because of Gerard 't Hooft. Not that I closely cooperate with him, for Gerard doesn't work together with anyone. His remarkable power is his totally individual stand alone way of thinking. He's very critical and we of course don't always agree on the problem of quantum gravity, but what I find very special about him is that he does not only attend colloquia and seminars, but he also visits talks by master students and he participates in their discussions. You name me another Nobel laureate who does such things. Gerard is really a part of the spirit of the place, which makes it extra encouraging to work here."

'This is not the only place in the world where it is assumed girls won't do well in exact sciences. What's worse, I think, is that people don't even acknowledge there's a problem.'

Renate Loll turned out to be in the four years since her appointment in Utrecht not only an eminent scientist herself, but also an enthusiastic advocate for more women in science.

"The position of women lies close to my heart. In the bètahoek I find the situation in the Netherlands especially shocking. In Germany the matter is freely discussed, but here things are even worse. Not only is the idea almost absent that girls could sometimes do well in exact sciences. Still more terrible, in my opinion, is that almost no one even thinks this is a problem. My male colleagues are very dear to me, and it is also not the case that they are against women, but they have no idea how male the system is in which they function and how that disadvantages many women."

As coordinator of the Enrage (European Network or Random Geometries) - network of the European Union Renate Loll have meanwhile found a way to give a boost to female scientists, she tells.

"It concerns a network of scientists who in several areas use the same type of geometrical techniques that I do in my study into quantumgravitatie. One of the objectives of that network is to promote the participation of women in exact science. You can take differing views concerning Europe, but the European Union have a very enlightened idea concerning women in science. In Brussels they are more progressive than in some of the Member States.

In all European programmes, concern for the position of women is an explicit priority. But what do you think happens as a result? Generally it means that in a research proposal of sixty pages somewhere near the end it says: by the way, we have someone in our network who pays attention to the women. Totally ridiculous. In my network I've made more effort to include women. Of the thirteen groups in Enrage, there are three in which excellent women play a prominent role. To all three I've offered extra as an inducement.

Renate Loll has herself had to overcome the necessary obstacles: "I was the kind of little girl that is already taking apart radios to see how they worked, but I thought a long time about what I would would do in the university. Then I thought: why don't you start with physics, that can't be a bummer. My parents thought it was a fine idea, but I got little further support from my surroundings, not only during my study, but also afterwards. I as a woman really have had fight to survive in science. That I didn't get a steady job until I was 39, speaks volumes.

Superstring theory

According to superstring theory, the most elementary particles in the universe are not points, but a kind of trembling elastiekjes, of which the ultrasounds occur to our as particles, such as electrons and photons. Although the theory seemed initially a promising candidate the antagonism between relativiteitstheorie and quantumtheorie, becomes always more clear bridge that she ensures for its part new problems. The most serious complication is that according to this theory our world --- without we see something of it in daily life --- belongs to a universe of ten or more dimensions. Perhaps our three-dimensional universe floats in higher dimension surroundings - in the same way that a flying carpet of two dimensions floats in three-dimensional space ---- separated from a shadow world, which might be only a few tenths of a millimeter distant from ours, as Spinoza-winner Robert Dijkgraaf vividly described it not long ago.

The solution for this problem will probably come from a totally unexpected direction.

Although Renate Loll is carefull to put it circumspectly, so as not to offend any of her colleagues, it is clear that she does not see much bread in research in this direction.

"At the beginning, superstring theory looked simple, and as a result, very attractive, but gradually complications have more and more appeared, as a result of which I now find it a rather far-fetched theory. Moreover is very unclear if the string approach will lead somewhere. For this reason I prefer my own treatment."

Those have, moreover, already produced concrete results.
Just like Renate Loll also Nobel Prize winner Gerard t Hooft has not been persuaded of the correctness of string theory. But whether the approach of his Utrecht colleague is correct, remains for him an open question.
"Renate clearly made progress last year, but she is still not there by a long ways. It is even the question if she is on the right track, as concerns quantum gravity. Although I myself am exploring a different solution in the direction of quantum gravity, I find that superstring theory at this moment still holds the best hand of cards. They have meanwhile encountered a number of annoying obstacles, but nevertheless that treatment [stringtheory] is still concrete and more structured than other attempts to reconcile the relativiteitstheorie and the quantumtheorie with each other.
This does not means that Renate cannot make it go right in the end. My philosophy is: let everyone muddle on. She especially should continue with what she is working on, because the solution for this problem will probably come from a completely unexpected direction.
Erik Hardeman
Appeared on 13-10-2005 in Ublad 7 (37).

 

[Kalimaa23]

The translation actually looks pretty good. If you want, I will write up a cleaner version.

 

[marcus]

The translation actually looks pretty good. If you want, I will write up a cleaner version.

I'd be delighted if you would like to do this----either write up a corrected version in full or, if you only want to correct some paragraphs or sentences, just post the corrected PART of the whole thing. (then I can enter the changes you suggest and save you the trouble of posting the entire article)

Please do whichever you prefer, Dimitri, and depending on what you have time for (I think you must be fairly busy with studies these days!)

There are probably many mistakes and you will find more of them the more you look. But here is one that has been bothering me, and I wanted to ask a Dutch speaker about it:

Right at the end, I have 't Hooft saying this:

"This does not mean that Renate cannot make it go right in the end. My philosophy is: let everyone muddle on."

I worry that the first sentence in the Dutch is an idiom or folk-expression.
The translation should maybe be more colorful or humorous. Like

"It could still be that Renate holds the right end of the stick! My philosophy is: let everyone muddle on."

I was not able to make clear sense of the original Dutch---you will see it right at the end where 't Hooft is talking.

thanks for any help!

 

[Andre]

"Maar dat wil niet zeggen dat Renate het niet bij het rechte eind kan hebben. Mijn filosofie is: laat iedereen maar aanmodderen. Zij moet vooral doorgaan met waar zij mee bezig is, want de oplossing voor dit probleem komt waarschijnlijk uit een hoek van waaruit we hem totaal niet verwachten."


But it doesn't mean that Renate could not be right. My philosophy is to let everybody continue doing their things. She should continue pursuing her research, because the solution for this problem might emerge from a perspective the least expected.

 

[marcus]

Thanks Andre!

Dimitri and Andre (any other Dutch speakers?) please suggest any corrections, or point out mistakes in the current draft.

 

[Andre]

You're welcome. Here is the intro reworked a bit:

Renate Loll (43) has been working in Utrecht for four years now. She has become an eminent scientist and an enthusiastic advocate for more women in science. She received three million euro from Brussels for (creating?) a European network and also a “Vici”- grant of 1.25 million euro last year. Enough money to keep searching for the holy grail in physics.

A vacuum, which is nevertheless not empty; a space time consisting of bits of foam; and our three-dimensional universe that is actually four-dimensional. The reality that Renate Loll studies is loaded with of paradoxes and contradictions. In her office (work-room) in the Minnaert - building, the German born lady showed full appreciation for the confusion of her interviewer.

"It is not easy to explain my research. To put it briefly, I’m looking for the structure of space-time. But it requires abandoning the “common sense” idea first, that we live in a three dimensional world with a single clock is ticking the same time for everyone. It’s a very useful assumption for every days life. However Einstein demonstrated with the theories of relativity, that there is no fundamental distinction between space and time. What one person may perceive as a time interval, could appear to be a part of space for another observer. In fact we live in a four-dimensional reality, according to Einstein, space-time.

 

[Timbuqtu]

Some remarks:

.., the German woman cleared up her interviewer's misconceptions. ->
..., the German woman shows her total understanding of the interviewer's confusion.

Now we couple that with an imaginary microscope which examines space time. -> Now suppose we examine the spacetime with an imagenary microscope.

We still have no precise idea how this happens, but it seems that, on the Planck scale of 10 to the minus 35 meters, spacetime itself starts to deform. -> We still have no precise idea how they behave, but it seems as though they themselves start to deform the spacetime.

It took years of struggling with this, before ... -> Years ago ...

... to discover the consequences of that idea. -> ... to work out all consequences of that idea.

'This is not the only place in the world where it is assumed girls won't do well in exact sciences. -> Not only is the thought nearly absent here that girls could do well in natural sciences.

... some of the Member States -> ... what Member State so ever.

Those have, moreover, already produced concrete results. -> (belongs to Loll's quote)

Although I myself am exploring a different solution in the direction of quantum gravity, ... -> Although I myself am looking for the solution in the area of black holes, ...


These paragraphes I've rewritten a little:


In all European programmes attention to the position of women counts as an important assesment criterion. But did you think that one feels addressed by this? Generally in a research proposal of sixty pages it comes down to a note in the back: by the way, we have someone in our netword who pays attention to the women. Totally ridiculous. In my network I've made more effort to integrate this. Of the thirteen groups in Enrage there are three, in which excellent women play a prominent role. I've offered all three of them an extra doctoral student position.

Renate Loll herself had to overcome several obstacles: "I was the kind of girl that at young age was already taking apart radios to see how they worked, but I thought a long time about what I would do at university. Then I thought: why wouldn't I just start studying physics? My parents found it alright, but further I have gotten little support of my surroundings, not only during my study, but also afterwards. As a woman I really have had to fight to survive in science. That I didn't get a permanant job until I was 39, is enough indication.

Superstring theory

According to superstring theory, the most elementary particles in the universe are not points, but a kind of trembling rubber bands, of which the vibrations occur to us as particles, such as electrons and photons. Although the theory seemed initially a promising candidate the reconcile the discrepancies between the theory of relativity and quantumtheorie, it becomes ever more clear that the theory leads to new problems. The most serious complication is that according to this theory our world --- without us noticing anything of it in daily life --- belongs to a universe of ten or more dimensions. Perhaps our three-dimensional universe floats in higher dimension surroundings - in the same way that a flying carpet of two dimensions floats in three-dimensional space ---- separated from a shadow world, which might be only a few tenths of a millimeter distant from ours, as Spinoza-winner Robert Dijkgraaf vividly described not long ago.

 

[Andre]

And my impression of the second part:

Now, suppose that we investigate that space time with an imaginary microscope. You would expect that on a certain very small scale, beyond that of the known smallest particles, there is no more matter present between those elementary particles, it would be an absolute vacuum. But the quantum theory, developed in the 1920s to explain what’s happening on that scale, tells a completely different story. This area is supposed to be like a big sea, in which particles emerge and decay continuously.

Those so called quantum fluctuations happen on millions of orders of magnitude smaller scales than the currently smallest known particles, the quarks (on a scale of 10^-19 meter). We still have no exact idea how those particles behave, but it appears that, on the Planck scale of 10^-35 meters, space time itself starts to distort. It will not be easy to verify this experimentally. Our particle accelerators will never be able to show us what happens at this very small scale and the relativity theories don’t explain events at that scale.

The major unresolved paradox in modern physics is that there are two different theories, both describing a part of physical reality in an very elegant manner. But they are based on totally different premises making them utterly incompatible. Therefore, scientists have been searching for the Holy Grail of physics, for many years now, which will explain this paradox by finding the common denominator for the behavior of the large scale structure of the cosmos (explained by the relativity theories) and that of the smallest particles (explained by the quantum theory). This would be the theory of quantum gravity (also: quantum gravitation),

Physicists agree that the key for such a theory is an adequate description of the structure of the space time, but the solution is pursued in several different ways. Many colleagues of Renate Loll assume that superstring theory is the most promising for this integration of the relativity theories with the quantum theory, but she herself prefers an approach that doesn’t require the presumption that there are more than four dimensions.

"I’m trying to create a model that realistically explains the space time of both the quantum scale and the cosmic scale. Since high energy fluctuations happen on the smallest scale, it appears that its space time is highly bend. But this is only conceivable if we assume that the space time is extremely distorted, or has been torn to multiple pieces (flecks), the quantum foam. The big problem, however, is that there is no theory capable of explaining how the sum of all those microscopic small scrap pieces of quantum foam produces a beautiful continuous four-dimensional reality in the macro world. So far, all attempts to construct such a theory have failed. Sometimes the end result would be a two-dimensional world, and sometimes a world with an infinitive number of dimensions."

 

[Kalimaa23]

Well, here you have it. I appologise for the spelling errors that are bound to be in there.


Looking for the holy grail

Renate Loll is looking for movement in de smallest particles

Renate Loll (43) has been working for four years in Utrecht. During that time she has become an eminent scientist and an enthousiastic advocate of women’s involvement in science. She has received more then three million Euros from Brussels for a European network, and last year she got a 1.25 million Euro vici-grant. More than enough money to continue looking for the Holy Grail of physics.

A vacuüm that isn’t empty; spacetime that consists fo little pieces of foam; and our three-dimensional universe that is a four-dimensional one. Thee reality that Renate Loll is studying, is full of paradoxes and contradictions. In her office in the Minnaetbuilding the German shows understanding for the confusion of her interviewer. “It’s not easy to explain what my research consists of. Very consisely put, I am looking for the structure of spacetime, but in order for you to understand what I mean by that, you first need to distance yourself from the common sense view that we live in a space of three dimensions, where a clock ticks in the same way for everyone. For our daily lives this is a very useful assumption, but Einstein has made it clear to us exactly one hundred years ago with his theory of relativity that there is no principal strikt separation between space and time. Something that someone sees as a piece of time, another sees as a piece of space. Actually we live, according to Einstein, in a fourdimensional reality : spacetime.”

“Suppose that we would investigate spacetime with an imaginary microscope. You would expect that on very small scales, beyond the last known elementary particles, there would be an absolute void. But quantum theory, that was developped in de twenties in order to explain what happens on this very small scale, tells us a very different story. According to this theory the vacuum is in reality an extensive “sea” , where particles are constantly created and destroyed. These so-called quantum fluctuations happen on scales that are millions of times smaller than the size (10-19m) of quarks, the smallest known elementary particles. We still do not have a precise idea of how they behave themselves, but it appears that on the so-called Planck scale of 10-35m they begin to deform spacetime itself. It’s not easy to determine this experimentally. Our particle accellerators will never be able to show us what happens on such a small scale, and the theory of relativity does not say anything about what happens on this scale.”

In fact, the great and still unresolved paradox in modern physics is that there are two theories, that both decribe in a very elegant manner a part of our physical reality. The are however based on so different principles that they are utterly incompatible. For many years theorists are looking for the holy grail of physics, the so called theory of quantum gravity that will resolve this paradox by describing the behaviour of large structures in the universe (explained by relativity) and that of the smalles particles (explained by quantum theory) in the same framework.

Amongst physicists there is the view by mutual agreement that the key to this theory lies in an adequate description of the structure of spacetime, but the solution is being sought in many different directions. Many colleagues of Renate Loll think that superstring theory is the best candidate to reconsile relativity with quantum theory, but she sees more promise in an approach that does not make it nescessary to assume that there are more than four dimensions.

“I try to build a model that describes both on the quantum scale as on the larger scale the structure of spacetime in an accurate way. Now it is believed that on the smallest scale that there are high energy fluctuations, that spacetime is curved to a high degree there. But that is only conceiveable if we assume that it is extremely warped or even ripped apart in uncountably many pieces of so-called quantum foam. The big problem is that there is no theory that can explain how the sum over all those little shards of quantum foam gives us our nice continuous four dimensional reality on macroscopic scales. All attemps to formulate such a theory have failed until now. Sometimes the sum gave us a two dimension world, sometimes it came out as a world with infinitely many dimensions.”

“Years ago I first got the idea that maybe the problem lay in the fact that many theorist had lost sight of the fact that at those very small scale there must also be a notion of causality, of cause preceeding effect. I took this to be an absolute condition for my calculations. After that, I have worked for years with a Danish and a Polish colleague to calculate all the consequences of that idea. And succesfully, because last year we showed in an article that computersimulations on the basis of minuscule pieces of quantumfoam, under the condition of causality, we indeed got a four dimensional universe. I can still remember vividly how it felt when we saw the outcome of the calculations appear. That was a very magical moment.”

Loll’s article has been received worldwide as a breakthrough towards a better understanding of the structure of spacetime. If it also offers prospects towards the long awaited theory of quantum gravity, is for many people still an open question. It is clear however that the management of the Utrecht Spinoza institute have made a good move in approving here. But why did a German researcher let pass an appointment at the reknowned Max Planck institutes in her native country in favour of the position of professor at Utrecht?

Loll : “I went to Utrecht in the first place because I could get tenure and a probably a professorship soon. But in part I also chose for Utrecht because of the reputation of this institute and because of Gerard ‘t Hooft. Not that I work closely with him, because Gerard does not work with anyone. His wonderful strenght is his utterly individualistic stand alone way of thinking. Hij is extremely critical and naturally we do not always agree on the problem of quantum gravity, but what I find very special is that not only does he go to colloquia and seminars, but also to the talks of masters students and discusses things with them. Name me one Nobel Prize winner who does that. Gerard truly is part of the spirit of the place. That makes it extra motivating to work here.”

In the four years since her appointment in Utrecht, Renate Loll has shown herself to be not only an eminent scientist, but also an enthousiastic advocate for a higher degree of women in science. “Women’s position is very important to me. I find the situation in the exact sciences in the Netherlands absolutely shocking. In Germany things were pretty bad, but it’s much worse here. Not only is the thought that girls could be good at exact science completely absent. Worse is that there isn’t even a realisation that there is a problem. My male colleagues are very dear to me, and it’s not that they are opposed to women, but they have no idea how masculin the system is in which they function and how it disadvantages women.”

As coordinator of the so-called Enrage (European Network of Random Geometries) network of the European Union Renate Loll has found a way to give female scientist a little support, she tells us. “It’s about a network of scientist who use the same geometric techniques that I use in QG in different fields. One of the goals of the network is to increase the participation of women in the exact sciences. You can have different views on Europe, but the EU has some very enlightened ideas about women in science. They are more progressive in Brussels then in any of the member states”

“In all European programs attention for women’s position is an explicit criterium. But did you think that anyone cared about it? Usually it comes down to writing somewhere at the end of a sixty page research proposition by the way, we have someone in our network who is responsible for the women. Completely ridiculous. In my network I’ve been trying to integrate this more. Of the thirteen groups in Enrage we have three where women play a prominent role. I gave all three of them an extra PhD grant.”

Renate Loll herself has had to conquer obstacles herself. “I was one of those young girls that was pulling radios apart, to see how they work but I had to think long about what I was going to do at university. Then I thought : Why not take up physics, it could never hurt. My parents were fine with this, but from the rest of my environment I got little or no support, not only during my studies but afterwards as well. I really had to struggle as a woman to make it in science. That I only got a permanent position at age 39 says a lot about that.

Superstring Theory

According to superstring theory the most elementary particles in the universe do not consist of points, but of a kind of vibrating ellastic bands, whose vibrations manifest themselves as particles, like electrons or photons. Although the theory initially seemed to be a promising candidate to bridge the gap between relativity and quantum theory, it seems to be more and more clear that the theory has her own share of problems. The most serious complication is that according to this theory our world is part of a ten dimensional universe, without us noticing in our everyday lives. Possibly is our threedimensional universe floating through higher dimensions, in the same way as a two dimensional flying carpet is flying throug three dimensional space, separated from a shadowworld that may be only a few tenths of a milimeter away, as Spinoza winner Robert Dijkgraaf recently decribed.

Altough Renate Loll is careful with her formulation as to not antagonize any of her colleagues, it is clear that she does not think much of this line of research. “Initially, superstring theory looked to be very simpel and therefore attractive, but graduately there emerged more and more complications, making me to find it quite a far fetched theory now. In addition it is unclear wether the string approach will lead us somewhere. That’s why I favour my own approach. That at least has produced some concrete results.”

Gerard ‘t Hooft, just like Renate Loll, isn’t at all convinced by string theorists. But wether the approach of his colleague from Utrecht is correct, is still a question according to him. “It is clear that Renate has made progress the last few years, but she’s not there yet. It’s even the question wether she is on the right track concerning QG. Although personally I tend to look in the direction of black holes I think that string theory still has the best hand. We have hit a number of obstacles, but none the less is that approach still more concrete and structured than other attemps to reconsile GR and QT. But that doesn’t mean that Renate couldn’t be right. My philosophy is, let everyone muddle on. She should continue with what she is doing, because the resolution of this problem will probably come from an unexpected direction.”

Do I get a cookie now? :shy:

 

[marcus]

Do I get a cookie now? :shy:

You should get one, except I have no way to dispense baked goods. This reads clearly and naturally, now. more or less as if it had been written in English. Thanks, Dimitri!

Thanks also to Andre and Timbuqtu! I am enthused that a spontaneous collaboration happened on PF, producing such a good result.

Dimitri, unless you tell me not to (post or send PM if you don't want this) I would like to simply copy your translation into the "Quantum Graffiti" thread, with your byline. This would let me correct minor spelling error.
The "Graffiti" thread is more cumulative and persistent, and I think this English version of Eric Hardeman's article is worth keeping. So if it is OK with you I would like to do that------this special purpose translation thread will likely just drift away, if there is no more discussion. Let me know if you don't want me to copy and correct spelling.

Thanks everybody. this was really great. I would put a lot of smileys but I wanted to be dignified.

 

[Kalimaa23]

By all means, do so.

 

[turbo]

Years ago I first got the idea that maybe the problem lay in the fact that many theorist had lost sight of the fact that at those very small scale there must also be a notion of causality, of cause preceeding effect. I took this to be an absolute condition for my calculations.

Yes! Also crucial is the concept of locality. Gravity is not some spooky action-at-a-distance force. It is the result of the interaction of matter with the local frame. The quantum vacuum is not a passive backdrop, but is conditioned by the matter embedded in it.

...Thereby it (GR) attributes to the ether, varying from point to point, the metric and the dynamical properties of the points of matter, which in turn are determined by physical factors, to wit the distribution of mass or energy respectively. The ether of the general theory of relativity therefore differs from that of classical mechanics or the special theory of relativity respectively, in so far as it is not 'absolute', but is determined in its locally variable properties by ponderable matter.