Almost a decade ago, I made an asymmetric bet against Adam Falkowski, a particle phenomenologist straightaway inward Paris. He claimed that supersymmetry wouldn't hold upward constitute earlier a deadline in addition to I claimed it could be. If it were found, I would remove hold won $10,000. If it weren't found, I would pay $100. So it was a 100-to-1 bet, basically implying the consensus probability of the early on plenty supersymmetry uncovering at 1%. I accepted the bet because my subjective probability of a SUSY uncovering was much higher than 1% in addition to I notwithstanding intend it was reasonable – in addition to an analogous supposition is notwithstanding reasonable for the side yesteryear side collider.
The deadline was defined a chip arbitrarily – but it was "after the results of at to the lowest degree 30/fb of the information at pattern liberate energy are collected". The pattern liberate energy was \(14\TeV\) in addition to \(8\TeV\) is clearly lower – the collisions at this lower liberate energy may make SUSY particles virtually 10 times less often than those at \(14\TeV\) – but \(14\TeV\) is unopen plenty to \(13\TeV\) thus it's obvious that those 35/fb at \(13\TeV\) that nosotros remove hold are basically equivalent to 30/fb at \(14\TeV\). So right straightaway it's the ideal balanced minute that almost just agrees alongside the weather condition of our bet, I think, in addition to because supersymmetry hasn't been discovered yet, I should pay $100 to Adam.
As I remove hold already mentioned, this lost bet is a technicality for me in addition to doesn't alter my belief that supersymmetry somewhere inward Nature, beneath the Planck scale, is really probable in addition to SUSY roughly the corner is e'er a possibility. I am sure that many of you lot concord that the reverse resultant would hold upward means to a greater extent than interesting – from the fiscal viewpoint, from the viewpoint of our TRF community, in addition to because of the excitement it would create amidst physicists.
So I desire to transportation him his $100 – although, obviously, there's notwithstanding a potential that some game-changing newspaper based on the same dataset volition hold upward published inward the future. This piddling transfer would remove hold taken house if Falkowski had a PayPal draw organization human relationship or could convey goods from Amazon etc. But he must alive at some uncivilized house of the globe that is decoupled from all the technological in addition to fiscal progress, amidst the sheep who facial expression for, eat, in addition to purpose lipsticks that tourists randomly threw away – it is inward Paris, equally I remove hold mentioned – in addition to he prefers the ancient transnational banking concern transfers over things similar PayPal, Amazon etc. that he doesn't desire to acquire involved with.
I could transportation a banking concern transfer to French Republic – inward a banking concern draw organization human relationship of mine, it's a ascendance that exists inward the online banking – but it's been non tested. I don't desire to transportation this coin inward ways that are thus untested, or examine them yesteryear smaller amounts etc. If person finds it prophylactic in addition to slowly to transportation payments to French banking accounts in addition to tin convey a PayPal payment from me or a $95-$105 plus transportation bundle from Amazon.com inward the U.S. (with products according to his or her choice) equally a compensation, delight allow me know.
This aught resultant of the post-Higgs-discovery LHC experiments hasn't surprised us. It's non anything nosotros could remove hold been unprepared for. People were extremely prepared for it – although they hadn't wanted it: the outcome has often been referred to equally the Nightmare Scenario. The run of the 6,000 people at the LHC since Summer 2012 has almost the same value equally the declaration "the SM is notwithstanding OK, motility on". H5N1 secretarial assistant would type this judgement for a cheaper salary than $10 billion. The Standard Model was a theory that worked upward to energies upward to \(200\GeV\) or thus – in addition to needed particles of similar masses (top quark, massive gauge bosons, Higgs boson) – in addition to it could remove hold broken downward right to a higher house \(200\GeV\) in addition to hold upward extended or supplemented or replaced alongside a broader theory. But it didn't happen. The same Standard Model industrial plant upward to \(1\TeV\) or a chip higher. Just to hold upward sure, different types of proposed novel particles are excluded to different energies inward different scenarios in addition to lots of particles lighter than \(1\TeV\) may notwithstanding exist, of course.
It's non a sudden contradiction alongside anything nosotros know virtually physics that the Standard Model remained isolated, equally James Wells et al. in addition to Jon Butterworth remove hold called it.
Why remove hold many particle phenomenologists preferred to believe that something else should remove hold been discovered along alongside the Higgs boson or shortly subsequently the Higgs boson? The declaration basically boils downward to i parameter, the Higgs volume \(m_h\) or the electroweak scale \(v\) (the vacuum expectation value of the Higgs field). They are much (fifteen orders of magnitude or so) smaller than the cardinal scales of Nature – which are arguably unopen to the Planck volume \(10^{18}\GeV\). And the "generic" value of this ratio would hold upward "of companionship one" inward a natural theory. The scalar bosons' masses should hold upward driven towards the heaviest volume scale inward physics, the Planck scale, yesteryear whatever quantum corrections unless in that location is something that changes the rules of the game in addition to keeps the Higgs boson (along alongside all the massive simple particles nosotros know) much lighter.
But let's facial expression a chip to a greater extent than closely. The Higgs vev \(v\) equally good equally the Higgs volume etc. are basically calculated from the Higgs potential\[
V(h) = \frac{1}{4}\lambda h^4 - \frac{1}{2}\mu^2 h^2
\] It's the business office that looks similar the champagne bottle's bottom (in the showtime world) or Landau's buttocks (in the 2nd world) or the Mexican chapeau potential (in the 3rd world). And yes, the value of \(\lambda\) is of companionship one, inward some normalization unopen to i quarter. (Exercise: abide by what it is inward my conventions.) Set the derivative \(V'(h)\) to null in addition to you lot volition abide by that the minimum of the potential i.e. the vev is at \(v^2 = h^2=\mu^2 / \lambda\). Calculate the 2nd derivative to encounter that the volume is of companionship \(\mu\) again, \(m_h\sim \mu\).
OK, the value of \(\lambda\) is of companionship one, equally I mentioned, in addition to completely "natural" patch it's only the value of the cardinal parameter \(\mu\) that looks unnaturally small. We may write it as\[
\mu^2 \sim 10^{-30} m_{\rm Planck}^2
\] The coefficient equally it genuinely appears inward the Lagrangian, namely the foursquare (tachyonic) volume term, is thirty orders of magnitude smaller than the cardinal unit of measurement alongside the same units. That's an apparent fine-tuning. However, this pocket-sized value could resultant from some instanton-like or otherwise naturally pocket-sized effect. Also, in that location could notwithstanding hold upward novel physics or superpartner masses at \(\Lambda=3\TeV\) or thus inward which illustration it would brand feel to write\[
\mu^2 \sim 10^{-3} \Lambda^2
\] OK, thus the whole mystery of the "isolated Standard Model" could hold upward just virtually i issue inward the Lagrangian that is virtually \(0.001\) times its generically predicted value. The probability that a random issue uniformly distributed betwixt \(0\) in addition to \(1\) is smaller than \(0.001\) is \(0.001\), too. It's unlikely but non insanely unlikely. This pocket-sized probability corresponds to some slightly than higher 3-sigma noise.
So you lot tin say that all the "surprising" isolatedness of the Standard Model is basically just a 3-sigma or thus deficit inward the squared Higgs mass.
It's non a large bargain in addition to because the explanations why the value is pocket-sized may hold upward clever, instanton-based, or otherwise naturally refuting the supposition that the distribution for \(\mu^2\) is uniform, the deficit could really good hold upward much less than iii sigma, too. And fifty-fifty if it were iii sigma or higher, you lot could also refer to the anthropic thinking that – fifty-fifty when used equally a co-argument – may brand the smallness facial expression much to a greater extent than natural than it would facial expression otherwise.
I desire to brand you lot sure that i time \(\mu\) is comparable to \(100\GeV\), everything else volition be, too. I've told you lot why the Higgs vev in addition to Higgs volume are comparable to \(\mu\) for \(\lambda\sim O(1)\). But the W-boson in addition to Z-boson masses may hold upward seen to hold upward \(v\) times some gauge couplings which are also of companionship one, thus these masses are also of companionship \(\mu\), in addition to the fermion masses are at most \(\mu\) or thus (like the acme quark) in addition to by in addition to large equal to this constant multiplied yesteryear the Yukawa coupling constants (that are smaller than one).
Again, if you lot filed a complaint alongside Nature virtually the "miraculously, unacceptably tiny" value of the simple particle masses etc. relatively to the Planck volume alongside Mother Nature, She would ignore your complaint. You're just a outpouring state of strings that has no right to complain. And I intend that She would hold upward fifty-fifty morally justified non to make a damn virtually your complaints because it may hold upward just a 3-sigma deficit inward the value of a unmarried coefficient inward the Lagrangian, \(\mu^2\).
New physics at the \(100\TeV\) collider is possible in addition to well-motivated but I would only motility into a similar bet equally the i SUSY bet against Adam Falkowski. It's inward no means guaranteed that in that location must hold upward novel physics. With such a bigger collider, the deficit equally "calculated" to a higher house could increment to 4-sigma but it's notwithstanding no large bargain in addition to alongside some hidden patterns violating the supposition virtually the uniformity of \(\mu\), the deficit may genuinely hold upward much smaller or completely absent.
Low-energy supersymmetry is almost the only other form of physics that would explicate smallness of \(\mu^2\) without requiring some "new nearby physics" to explicate the smallness of its ain novel parameters.
But those who thought it was "almost certain" that the Standard Model has to hold upward accompanied alongside some additional novel physics – different than SUSY – were implicitly assuming (perhaps without fifty-fifty realizing or at to the lowest degree acknowledging it) that this draw of reasoning basically implies that the whole logarithmic axis betwixt the electroweak scale in addition to Planck scale has to hold upward filled alongside novel scales in addition to segments of physics. The Standard Model must hold upward accompanied yesteryear some other model, e.g. the Nude Model. But the Nude Model won't ever rest alone, either. So in that location would remove hold to hold upward some other model at slightly higher energies, the Horny Model. But that model also has scalars that are pocket-sized in addition to unexplained thus in that location has to hold upward the nearby Morality Police Model. And thus the Constitutional Court Model, in addition to thus on, upward to the model of quantum gravity nigh the Planck scale.
I abide by this scenario alongside lots of scales possible but rather unnatural according to my full general interpretation of the give-and-take "natural". If the issue of scales (layers of the physical onion) betwixt the everyday life scales in addition to the Planck scale were much greater than one, it would hold upward just some other parameter that should naturally hold upward of companionship i but it isn't. So when you lot separate the desert betwixt the electroweak in addition to Planck scale to 16 pieces, it's similar a pizza cutting to 16 pieces. Madam, would you lot similar me to cutting the pizza to 8 or 16 pieces? The blonde answered: Only eight: 16 would hold upward also much for me to eat.
Madam, I intend that fundamentally, the cutting doesn't genuinely alter the overall severity of the occupation (or the amount of food).
So I remove hold never genuinely thought – in addition to I notwithstanding don't intend – that adding also many scales (layers of the physical onion) that are also unopen to each other on the liberate energy scale makes the physical painting present to a greater extent than natural. You know, the gap betwixt the electroweak scale in addition to the Planck scale is a demonstrable fact that nosotros already know. So a deep physical theory has to explicate this pocket-sized issue inward i means or another. Having an onion alongside lots of sparse layers is just i extreme strategy to explicate it. It's non the only i in addition to it's non a especially natural or elegant one, either, I think.
If in that location is a large desert betwixt the electroweak scale in addition to the Planck scale that is explained yesteryear some theory that makes \(\mu^2\) vanish inward the leading approximation (conformal symmetry?) but produces some pocket-sized \(\mu^2\) yesteryear some naturally pocket-sized (e.g. instanton) effects, it's fine alongside me. I notwithstanding intend that low-energy SUSY is ameliorate than a fundamental, slightly broken conformal symmetry inward the spacetime, but I am non a bigot in addition to there's no enterprise evidence that the smallness "has to be" explained yesteryear i type of an explanation or another.
Here you lot remove hold a logarithmic nautical chart of the masses of known simple particles. Note that photons, gluons, in addition to gravitons are fundamentally "exactly massless" equally far equally all experiments in addition to theories extracted from them go. On the other side, in that location is some reduced Planck scale nigh \(10^{18}\GeV\). But what virtually the massive particles? The heaviest ones are nigh \(100\GeV\), the acme quark, the Higgs boson, in addition to the massive electroweak gauge bosons. And thus you lot remove hold all the charged fermions alongside smaller in addition to smaller masses downward to the electron at \(5\times 10^{-4}\GeV\). The widest ratio of the neighbors' masses is virtually 15 inward this quasi-continuum.
Beneath the electron, in that location is some other gap (the teeth inward the diagram hateful that half dozen floors are omitted!) in addition to below this gap, you lot abide by neutrinos alongside masses comparable to \(10^{-11}\GeV\). You encounter that the masses of an electron in addition to the neutrinos differ yesteryear seven orders of magnitude in addition to there's a non thus pocket-sized desert inward between. That's why I intend that nosotros should say that a desert of this magnitude – in addition to mayhap fifty-fifty a bigger i – isn't a large deal. But the LHC hasn't genuinely proven whatever "really large gap" thus far. If the "next heavier" particle to a higher house the (so far most massive) acme quark were just 15 times heavier, in addition to the ratio of 15 wouldn't hold upward unprecedented, equally I remove hold mentioned, the side yesteryear side novel particle would hold upward roughly \(3\TeV\) inward mass. There are lots of scenarios similar that which haven't excluded yesteryear the LHC yet!
This nautical chart of the particle masses is mixing apples in addition to oranges, a particle physicist would say, because the source of masses is really different for the different particles. I remove hold sketched that the masses of all the particles heavier than neutrinos practise boil downward to the parameter \(\mu\) subsequently all. But the neutrino masses don't. The Majorana neutrino masses can't hold upward obtained from a renormalizable volume term because that wouldn't hold upward gauge-invariant. They tin only hold upward extracted from some non-renormalizable interactions – which include a higher might of the Higgs land \(h\) that accompanies \(v\) – in addition to their magnitude is extracted from some physics at a really high liberate energy scale, e.g. yesteryear the "seesaw mechanism".
Such mechanisms in addition to mayhap fifty-fifty to a greater extent than clever ones are in all likelihood used yesteryear Nature at many other places. They may guarantee that whatever potential contradiction or unnaturalness of pocket-sized parameters is fifty-fifty to a greater extent than innocent than what it looks like.
To summarize, I don't intend that the aught results of the 4+ post-Higgs years of the LHC contradict some theories or principles virtually Nature that nosotros remove hold learned. The uncovering of novel particles was possible but it was never guaranteed in addition to the belief that it would emerge has e'er been driven yesteryear a wishful thinking to i extent or some other (or yesteryear someone's innovation to acquire out famous equally chop-chop equally possible). I postulate to emphasize that this see of mine is inward no means new. I've believed the same matter for decades. The fact that some parameters are equally pocket-sized equally \(0.01\) or \(0.001\) isn't a terribly strong hint of anything. After all, the ordinary fine-structure constant is \(1/137.036\) in addition to nosotros don't intend that this pocket-sized value proves some amazingly hard hierarchy occupation inward Nature. The constant \(\alpha\sim 1/137.036\) is pocket-sized partly because of \(1/4\pi\) that is naturally incorporated inward it, partly because of the smallness of gauge couplings or their ratio (angle) calculated from them, partly from RG running that makes electromagnetism intrinsically weaker at long distance, in addition to partly yesteryear some "slightly less than one" values of the cardinal gauge couplings at the GUT scale. There's only no "shocking", unexplained smallness of \(\alpha\).
The "at to the lowest degree moderate desert" to a higher house the Standard Model has acquire out a fact. The Standard Model physics has acquire out a chip lonely house but the Standard Model is consistent upward to much higher energies, plausible explanations for the relative smallness of the i dimensionful parameters exist, in addition to i only cannot derive whatever strong contradiction. One cannot brand whatever large decision – e.g. that the world requires the anthropic regulation – either. The estimated distance betwixt the Standard Model isle to the side yesteryear side islands or continents has only increased a bit. That's it. It's in all likelihood non an exciting plenty "story" but it seems to hold upward the truth, anyway.
Geological metaphor
I genuinely intend that the really analogy alongside the "islands" inward geology implies a similar conclusion, "not a large deal". Imagine that you lot abide by yourself living on an island. What's the distance of this isle from the closest other landmass – isle or continent – divided yesteryear the Earth's radius?
The naive naturalness consideration would Pb you lot to say that the distance betwixt continents is comparable to the Earth's radius – it's certainly truthful for Europe (or Eurasia) in addition to America or Commonwealth of Australia or Antarctica. The islands should hold upward uniformly distributed inward the remaining body of body of water or seas thus their distance from the nearby continent should hold upward comparable to the Earth's radius, too.
However, you lot abide by many to a greater extent than islands that are genuinely unopen to continents. For example, Hellenic Republic has lots of islands from which the illegal immigrants may swim to the European continent. It makes feel that the islands are genuinely closer to the continents: the waters are shallower nigh the continental beaches which makes islands – localized fluctuations of the height to a higher house null – to a greater extent than likely. Such a nearby landmass may serve equally a candidate for an "explanation" why your isle exists at all: it's some random fluctuation added side yesteryear side to some bigger nearby landmass.
However, some islands are really far from the continents or other islands, too. Their distance may hold upward comparable to the Earth's radius but it may also hold upward "in between", e.g. 500 km. How is it possible? Well, it's just possible. I intend that the argumentation inward the illustration of geology – why in that location are islands whose distance from the continents is either really pocket-sized or intermediate or comparable to the Earth's radius is qualitatively equivalent to the argumetation why \(\mu^2\) may hold upward really unopen to \(\Lambda^2\) of some novel physics, iv orders of magnitude lower, in addition to maybe fifty-fifty thirty orders of magnitude lower. Some islands are in that location equally disconnected pieces of nearby continents. Others are tiny continents yesteryear themselves. Some islands may resultant from the landing of an asteroid. Yet some other grouping of islands were libertarian paradises paid for in addition to built yesteryear Peter Thiel, in addition to thus on. The multifariousness of explanations of "islands of phenomena inward particle physics" may hold upward analogously various although you lot shouldn't pick my listing of causes literally.
The belief inward a clumping of islands in addition to continents (or other islands) is just a belief, non a really enterprise argument. And when applied consistently inside a theory of everything, it's basically equivalent to the see that the large oceans shouldn't be at all (or, inward physics, deserts are prohibited). The world inward which the "islands of physics" would hold upward densely distributed may facial expression to a greater extent than intriguing or exciting for some people but that doesn't acquire out far to a greater extent than likely. And the Universes alongside large deserts may hold upward non only probable but also really elegant in addition to intriguing, too. Their sexiness is of a different type than the sexiness of archipelagos nigh continents but it's really real. One must hold upward able to encounter that some hypotheses are just hypotheses in addition to they are driven yesteryear prejudices, non rational arguments, in addition to the belief that novel physics "must e'er hold upward roughly the corner" was e'er a prejudice.
It's possible but it's also possible that it's false.
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