Desperately seeking SUSY?

To date not a single supersymmetric particle (predicted) has been found.
Why - either our current particle accelerators cannot generate enough energy or Supersymmetry is just wrong. We'll have to wait and see.

Until String Theory gives us a single verifiable result, it should remain as pure speculation. At the moment people quote it as gospel. That should stop.

Desperately seeking SUSY?

To date not a single supersymmetric particle (predicted) has been found.
Why - either our current particle accelerators cannot generate enough energy or Supersymmetry is just wrong.

Well supersymmetry predicts that the first supersymmetric partner should be visible at the LHC. If it isn't supersymmetry is wrong. Which is standard scientific practice so there isn't anything wrong with it.

Until String Theory gives us a single verifiable result, it should remain as pure speculation. At the moment people quote it as gospel. That should stop.

Well that is how most people treat it in the majority of the world's universities. There are certainly those who are overzealous, but again string theory isn't that important in physics in general.

Although its seperate to String Theory, I'll stick my neck out and predict that the LHC finds not even a Squark (lightest supersymmetric particle). But guess what - they'll raise the bar yet again, and revise their mass of the Squark upwards, SUSY will not be dumped either, regardless of evidence (or lack of it). If we built an accelerator that could harness all the power in the universe and didn't find a SUSY they would still be able to revise the theory to account for lack of evidence.
I'd love to be wrong because that would mean we were on the right track and at least give a whole new direction to particle physics. So here's to finding Squark.

Physics used to be about providing Theory to explain what we observed through experience or experiment. Nowadays we seem to be coming up with theorys that are impossible to prove and have no grounding in observation, and are they even necessary? Nice maths though.........

Although its seperate to String Theory, I'll stick my neck out and predict that the LHC finds not even a Squark (lightest supersymmetric particle).

Why? I could say I'll stick my neck out and supersymmetry will be found. Without experimental results it's a pointless thing to say. It's not like the LHC is a horse race with odds-on favourites.

But guess what - they'll raise the bar yet again, and revise their mass of the Squark upwards, SUSY will not be dumped either, regardless of evidence (or lack of it).

Again, why would you think this? It sounds like you're conflating the Supersymmetry community with the String Theory community. The supersymmetry people have never given any indication that they'll do this. Frank Wilczek has said he's interested to see if it's correct or move on. Remember it's mainly an idea that was done and dusted in the 70s and 80s, so nobody has a big attachment to it. Supersymmetry is simply simply the final possible symmetry quantum field theory could posses, so it's interesting to check if it is right. Could you indicate why you believe the supersymmetry community will do these readjustments?

Physics used to be about providing Theory to explain what we observed through experience or experiment. Nowadays we seem to be coming up with theorys that are impossible to prove and have no grounding in observation, and are they even necessary?

"We" do? You've given one example of this with String Theory and one incorrect example with supersymmetry. It isn't a modern day phenomena, for instance see Kelvin's atomic knot theory. In fact the past 100 years and even the past 50 or 25 years have had an excellent track record for newly invented theories which were later confirmed. For example all the field theories in condensed matter.

Nice maths though.........

Well the maths of modern theories aren't really as intricate as the Mathematics of QFT from the 1940s. For instance supersymmetry is just an additional (bigger) symmetry group.

Why? I could say I'll stick my neck out and supersymmetry will be found. Without experimental results it's a pointless thing to say. It's not like the LHC is a horse race with odds-on favourites.

'Cause it's a bit of fun and provides a talking point. Also, although I like Supersymmetry (it's a lot more logical than string), something just doesn't feel right about it (now there's a scientific argument). Like you say we'll know soon enough hopefully.

Could you indicate why you believe the supersymmetry community will do these readjustments?

I could be wrong, but haven't the masses of SUSY particles been revised many times, usually after the latest accelerator has shown no "results"? Like I say - I could be wrong .

In fact the past 100 years and even the past 50 or 25 years have had an excellent track record for newly invented theories which were later confirmed. For example all the field theories in condensed matter.

Fair enough....

Quote:
Nice maths though.........

Well the maths of modern theories aren't really as intricate as the Mathematics of QFT from the 1940s. For instance supersymmetry is just an additional (bigger) symmetry group.

I was referring here to String Theory mathematics e.g. Calabi-Yau manifolds and other topological mathematics, etc. very interesting and will no doubt prove useful in other fields.

Just as a matter of interest - where does your bet lay? Are you a supporter of String or SuperSymmetry or Loop Quantum Gravity. I am not, as you've probably gathered, a Particle Physicist. I have nothing to base my assumptions on other than the books I have read (so I could be totally wrong). What I have learned has been self taught, so if I'm wrong blame my teacher. A lot of the problem I have with String Theory is where it flies in the face of Relativity Theory, namely gravity (curvature of spacetime - they seem to treat gravity as a newtonian force). So - where do you stand?

I have to say this is real interesting, John, you mention that you believe the LHC will not provide the particles they say it will and the they will simply say they need a bigger accelerator, they will surely have to say why?? they will not get away with simply making it up.
At least they have a theory which they are trying to prove, I suppose we'll have to wait and see the LHC results, presuming it doesn't generate a black hole that swallows us all up. :wink:

Dave,

I would love String Theory or SuperSymmetry to be correct, at least it would mean that we haven't been chasing ghosts for the last 30 years.

However the LHC will be providing data from October. It may be some years before we can say for sure but I do not beleive that String Theory will gain anything from the results. SUSY may be another matter, there is at least a chance that results may be obtained, and it would be my preferrred solution. However I think the SUSY Theory is full of holes and is not sustainable. Therefore the results "they" are looking for will not be forthcoming. The LHC is predicted to be within the energy range necessary to produce the lightest of SuperSymmetric particles (Squark). What do you think will happen if they don't find it.

As for the ridiculous postulation of miniature black holes from the stringers? This is a definite no-find. And Gravitons? Hah - again a rediculous notion. Did none of them understand Relativity? or am I just stupid (that may also be the case, in which case my butt may well be on display in Debenhams windows).

Whatever happens I am in no doubt that the LHC results will teach us a lot. Wether we want to learn from them is another matter - after all money and power is at stake. So I don't think String or even SUSY will be abandoned because of negative results.

(snip) I would love String Theory or SuperSymmetry to be correct, at least it would mean that we haven't been chasing ghosts for the last 30 years.

That may well be the case. Lee Smolin for one writes on why this may have happened in his excellent book "The Trouble With Physics".

Apart from a review of the current "landscape" and past examples where physicists have taken wrong turns, Smolins goes into detail on the politics of a research career. He mentions Groupthink (the tendancy for members of a group to start agreeing with one another) but at all times he is courteous to the string theorists - even though there is well-reported arrogance in the string theory community!

The book is an eye-opener. The chapters on String Theory are hard going but then again it is quite possible that String Theory is entirely nonsense!

A similar book criticising String Theory is "Not Even Wrong" by Peter Woit. The title is based on Pauli's ultimate put-down (Wikipedia puts it as: "to be not even wrong if it is based on assumptions that are known to be incorrect, or alternately theories which cannot possibly be falsified or used to predict anything").

Apart from a review of the current "landscape" and past examples where physicists have taken wrong turns, Smolins goes into detail on the politics of a research career.

I enjoyed Smolins Book on Loop Quantum Gravity. I must look up "The trouble with physics".
I have talked to some physicists at CERN and some of the techies involved and the stories they tell of the "backstabbing" and underhanded deals would leave you incredulous if you hadn't already spotted the trend. Don't doubt that particle physics is "THE" most political arena. Huge sums of money and power is at stake (physics is incidental - almost irelevant - which is why I make some of the claims in this post).

A similar book criticising String Theory is "Not Even Wrong" by Peter Woit.

Woits book is very convincing - I recommended it earlier in this post.

Can I ask you to define your stance on String et al. Do you think it is worth investing so much resources in? Some here have said that String is a small niche area - I don't think people recognise how influential it is in modern particle physics or how prevalent it has become. A PHDer looking for a position today almost has to be a "String Believer" to stand a chance - this is a very wrong starting position in my opinion.

I could be wrong, but haven't the masses of SUSY particles been revised many times, usually after the latest accelerator has shown no "results"? Like I say - I could be wrong .

No, for N=1 SUSY the LHC is the first accelerator which is within the energy ranges of the particle masses.

Just as a matter of interest - where does your bet lay? Are you a supporter of String or SuperSymmetry or Loop Quantum Gravity.

Neither. Quantum Gravity is a very technical area, I'm not really sure what the correct kind of idea should be. There are a lot of conceptual and mathematical issues at play here.

However I think the SUSY Theory is full of holes and is not sustainable.

It's a single extra symmetry on top of the Standard Model. The interest in is that it is the largest symmetry compatible with quantum field theory. Hence the interest in it is to see if our universe is as symmetric as it can be. We will see if it is or is not in the LHC. How is it "full of holes"?

Huge sums of money and power is at stake (physics is incidental - almost irelevant - which is why I make some of the claims in this post).

Huge sums of money and power? The entire global funding for String Theory in a given year is vastly exceeded by almost any other area of science. As for power, what power? You make it sound like they have subjegated nations. What is the power at stake?

Some here have said that String is a small niche area - I don't think people recognise how influential it is in modern particle physics or how prevalent it has become. A PHDer looking for a position today almost has to be a "String Believer" to stand a chance - this is a very wrong starting position in my opinion.

As a PHDer looking for a position today in particle physics, what I think of String Theory has never come up at all. In either interviews or in fact ever. Maybe a casual, "what do you think of it?", but nothing else. There are several areas of particle physics where you will never hear it mentioned and all of these areas have far more funding. Again one must remember that this is a largely American phenomenon. Take a look at some British universities and you'll easily see it doesn't dominate:
(a) Theoretical Physics
(b) Particle Physics
but rather it dominates Quantum Gravity research which is a niche area.

The LHC isn't just for string theory its going to be doing research in a couple of areas.And its better goverments spend money on this rather than going to war.What ever the case i'm sure LHC will make some interesting discoveries.

(snip)Can I ask you to define your stance on String et al. Do you think it is worth investing so much resources in?

Would "Not Even Science" be too bitchy! :wink: At least Dark Matter and Dark Energy seem testable (I have my doubts about them too!).

Don't get me wrong, I certainly don't think the LHC for example is a waste of money.

Smolin has much to say on choosing a research area other that String Theory. I don't envy any one choosing a career path in physics.