## Profile

Cliff Harvey
Attended Worcester Polytechnic Institute
Lives in Connecticut
28,671 followers|1,743,637 views

## Stream

### Cliff Harveyowner

Quantum Field Theory  -

Simple Recursion Relations for General Field Theories
http://arxiv.org/abs/1502.05057

This looks like an exciting development in the program of reformulating quantum field theory in full generality:

On-shell methods offer an alternative definition of quantum field theory at tree-level, replacing Feynman diagrams with recursion relations and interaction vertices with a handful of seed scattering amplitudes. In this paper we determine the simplest recursion relations needed to construct a general four-dimensional quantum field theory of massless particles. For this purpose we define a covering space of recursion relations which naturally generalizes all existing constructions, including those of BCFW and Risager. The validity of each recursion relation hinges on the large momentum behavior of an n-point scattering amplitude under an m-line momentum shift, which we determine solely from dimensional analysis, Lorentz invariance, and locality. We show that all amplitudes in a renormalizable theory are 5-line constructible. Amplitudes are 3-line constructible if an external particle carries spin or if the scalars in the theory carry equal charge under a global or gauge symmetry. Remarkably, this implies the 3-line constructibility of all gauge theories with fermions and complex scalars in arbitrary representations, all supersymmetric theories, and the standard model. Moreover, all amplitudes in non-renormalizable theories without derivative interactions are constructible; with derivative interactions, a subset of amplitudes is constructible. We illustrate our results with examples from both renormalizable and non-renormalizable theories. Our study demonstrates both the power and limitations of recursion relations as a self-contained formulation of quantum field theory.

Clifford Cheung, Chia-Hsien Shen, Jaroslav Trnka﻿
Abstract: On-shell methods offer an alternative definition of quantum field theory at tree-level, replacing Feynman diagrams with recursion relations and interaction vertices with a handful of seed scattering amplitudes. In this paper we determine the simplest recursion relations needed to ...
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### Cliff Harveyowner

Videos: lectures, interviews, panels  -

Ed Witten-2+1 Dimensional Gravity Revisited

This is a very important self-contained lecture by Witten regarding the famous correspondence between the symmetries of the  BTZ black hole in 2+1 dimension QG and the Monster symmetry group of the dual CFT (related to the Moonshine conjecture in Mathematics).

This famous correspondence was suggested by Witten around 2007 [1].

[1] Three-Dimensional Gravity Revisited

http://arxiv.org/abs/0706.3359

#Physics #Mathematics #quantumgravity  ﻿
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### Cliff Harveyowner

Quantum Field Theory  -

A great summary of some special QFT's descending from the (2,0) theory in 6 dimensions by .

(Many more of your posts would be greatly welcome here.)

Terminology and offsprings of 6d (2,0) SCFT

One of the main properties of 6d (2,0) SCFT of Lie gauge algebra of type g is that via its compactification on certain d-dimensional manifolds provides a geometrical description of certain lower 6-d dimensional Supersymmetric gauge QFTs of type g. Then you can establish a dictionary between observables of the Supersymmetric gauge QFTs and quantities defined on the d-dimensional manifold.

Depending on the construction and their characteristics the classes and sub classes of these 6-d dimensional theories have specific names. Here are the two important classes S and R:

Class S Theories

A Class S theory is the 4d SCFT theory obtained by compactifying 6d (2,0) SCFT on a 2d Riemann surface C with certain genus and with or without punctures (i.e. topological defects).

In that respect the 4d N=4 SCFT MSYM is a class S theory obtained by compactifying 6d (2,0) SCFT if the 2d  Riemann surface C is a 2-Torus T2.

Note that often people use the term Class S theories only for the N=2 SCFTs theories obtained by compactification (partially twisted) of the 6d (2,0) SCFT on generic Riemann surfaces with punctures (punctures are related to flavor symmetries of the 4d theory).

Basically this class of theories and their dualities were introduced in a seminal paper by Gaiotto [1].

Tg Theories

A Tg theory, with g denoting the gauge algebra g, is a class S special theory obtained by compactifying the type g 6d (2,0) on three-punctured sphere; it is usually called Tn theory when the Lie algebra g is of type An−1.

It has g^3 flavor symmetry.

Class R Theories

Class R theories are the 3-dimensional analogue of class S theories obtained by compactifying 6d (2,0) SCFT on special 3-dimensional manifolds M.

These are 3d N=2 SCFTs obtained via Chern-Simons Matter theories (CSM).

For their construction and the relevant dictionary between the 3d manifold M and the 3d theory refer e.g. to some of the original work in [2] and [3].

References

[1] N=2 dualities

http://xxx.lanl.gov/abs/0904.2715

[2] Gauge Theories Labelled by Three-Manifolds

http://arxiv.org/abs/1108.4389

[3] 3-Manifolds and 3d Indices

http://arxiv.org/abs/1112.5179

#Physics   #stringtheory  ﻿
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Has anybody been involved in creating class R variants for use with coordination chemistry? I'm looking for research dealing with electron momentum for quantized energy states.﻿

### Cliff Harveyowner

String Physics Discussion  -

A very interesting paper appeared on the hep-th feed yesterday morning, which seems to resolve a nagging 14-year mystery in string theory: What is the origin and justification of the pure spinor formalism for superstrings?

Twistor Origin of the Superstring
http://arxiv.org/abs/1409.2510v1
Nathan Berkovits (ICTP-SAIFR/IFT-UNESP, Sao Paulo)

This formalism is unique in organizing superstring calculations in a way that preserves both manifest spacetime supersymmetry as well as manifest worldsheet Lorentz invariance, and so it has proven to be more powerful than either of the two traditional formalisms.

“Unlike the RNS and Green-Schwarz formalisms, it has been successfully used to compute multiloop amplitudes involving both bosonic and fermionic states and to prove the quantum consistency of Ramond-Ramond backgrounds such as AdS^5 ×S_5. ...But despite several attempts, this pure spinor BRST operator was not obtained in a simple manner by gauge-fixing a worldsheet reparameterization invariant action. In this paper, an elegant geometrical origin for this formalism will be proposed and the pure spinor BRST operator of (1.2) will be obtained by gauge-fixing a simple worldsheet reparameterization invariant action. Surprisingly, this reparameterization invariant action will be constructed entirely from bosonic worldsheet variables, and the fermionic worldsheet variables θ^α and their conjugate momenta will come from ghosts and antighosts associated with the gauge fixing.”

This development strikes me as perhaps especially interesting in light of how powerful twistor variables have proven in understanding standard 4D gauge theories. A whole wealth of striking connections were unearthed after casting the physics in the proper variables, like a correspondence between scattering amplitudes and Wilson loops, whose current culmination seems to be the Amplituhedron geometry of N=4 SYM. This is just a vague hope but maybe clarifying the twistor origin of the superstring could prove to be a step on the way to some deeper understanding of string theory. One feature they have in common at this early stage is that supersymmetry emerges from a purely bosonic setup in both cases. On the other hand, I know of no particular reason that knowing the worldsheet origin of the pure spinor formalism should get us any further than knowing the formalism itself.

For more background on pure spinors see:
http://online.kitp.ucsb.edu/online/qcdscat11/berkovits2/
Nathan Berkovits - Recent Applications of the Pure Spinor Formalism﻿
Abstract: After introducing a d=10 pure spinor $\lambda^\alpha$, the Virasoro constraint $\partial x^m \partial x_m =0$ can be replaced by the twistor-like constraint $\partial x^m (\gamma_m \lambda)_\alpha=0$. Quantizing this twistor-like constraint leads to the pure spinor formalism for the ...
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A picture is worth a 1000 words which is good because I couldn't write a paper like this to save my life! #Studiousrealism﻿ #stingtheory﻿

### Cliff Harvey

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This is an awesome result by the , an apparently decisive observation of the first 'exotic' hadron consisting of at least four quarks.

(All other known combinations of the color-charged quarks come in sets of either 2 (mesons) or 3 (baryons, such as protons). Lone color charges are banned by the strong interaction.)

Observation of the resonant character of the Z(4430)− state
http://arxiv.org/abs/1404.1903
The LHCb Collaboration has reported today an analysis of about 25 200 B0 → ψ’Kπ-, ψ’ → μ+μ+ decays observed in 3 /fb of pp-collision data collected at √s = 7 and 8 TeV. The LHCb data sample exceeds by an order of magnitude that of Belle and BaBar together. The significance of the Z(4430)- signal is overwhelming, at least 13.9σ, confirming the existence of this state. The Z(4430)- quantum numbers are determined to be JP = 1+ by ruling out 0-, 1-, 2+ and 2- assignments at more than 9.7σ, confirming the evidence from Belle. The LHCb analysis establishes the, so called, resonant nature of the observed structure in the data, and in this way proving unambiguously that the Z(4430) is really a particle.

They measure it to have:
Mass:  4475 ± 7 MeV
Width:  172 ± 13 MeV
Amplitude fraction: (5.9 ± 0.9) %

LHCb confirms that the Z(4430) state observed by the Belle collaboration is a particle. It must be formed of at least four quarks.﻿
LHCb is an experiment set up to explore what happened after the Big Bang that allowed matter to survive and build the Universe we inhabit today. Fourteen billion years ago, the Universe began with a bang. Crammed within an infinitely small space, energy coalesced to form equal quantities of ...
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Do they know which four quarks are involved?﻿

### Cliff Harvey

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Heres a nice little summary of a fantastically under-appreciated insight in theoretical physics, which can be summarized by the simple slogan: Gravity is Yang-Mills Squared.

This is a prime example, and a relatively easy one to explain at that, of the stark connections between the two big frameworks of fundamental physics, gravity on the one hand and Yang-Mills theory describing the remaining 3 forces on the other. These kinds of connections are what puts theoretical physics in such a fascinating and exciting position. Despite the fact that the master theory that would fully explain these connections remains out of the reach of laboratory science, its impossible to study these established frameworks in any depth without noticing some of these dramatic clues lying around.

Explaining such "coincidences" should be a primary target of any putative master theory. String theory actually provides quite a bit of intuition and understanding to back these relations – roughly it corresponds to the fact that a closed string (associated with gravity) is essentially the same as two open strings (associated with Yang-Mills forces) joined into a loop. The relationship gets more complicated beyond the tree approximation, and it will certainly be more complicated in any configuration that could fully reproduce the richness of the world around us, but the point is that these ideas have helped to distill some of the essential connections between the two seemingly distinct kinds of forces. (Further reading: http://arxiv.org/abs/1312.1326 )

Explanatory power is the key benchmark for any prospective theory of physics, so if nature utilizes some completely different framework it should be possible to find it eventually, and derive equally good or better explanations for some of these features. However that may not be the case, and in the meantime it should surprise no one that the field continues to focus its energy on the ideas that produce such useful results and understanding.

I hope that further research will turn many more of today's "miracles" into tomorrows derived facts, and encouragingly, the list of miracles is still intimidatingly large.﻿
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There are a few more striking ways in which string theory insights have led to advances in pure QFT. I am collecting pointers and links to such here: http://ncatlab.org/nlab/show/string+theory+results+applied+elsewhere ﻿

### Cliff Harvey

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Theorist David Tong does on awesome 30-minute summary of what we know about early universe cosmology in Wonders of the Big Bang, his talk for . He explains the basic method of using particle models to predict the spectrum of the CMB, and describes various phase transitions that occurred during the first moments of the universe. He does a good job delineating what is actually established by experiment, especially by the Planck satellite most recently, versus what is speculative. He also alludes to the important distinction between conservative speculation versus more dramatic and assumption-ridden speculation.

Whats especially promising and exciting about this whole field is how it directly connects to extreme regimes of the universe that are otherwise pretty infeasible to probe with particle experiments. The big bang clearly isn't repeatable by humans, so obviously there is a fundamental limit of science we're up against here, but speculative models that attempt to complete the account from the Standard Models perspective can still make predictions that will be tested by more detailed CMB measurements, at least up to a point.

A good description of the inflationary period seems to require use of a scalar potential – the inflaton – and so in broad terms this may be related to the Higgs mechanism which was just verified last July. While we can't say for sure if there is any useful relation to draw between them, its certainly possible that we will one day understand a common origin for these two pieces of information about Nature's scalar sector. (Michio Kaku was once rightly called out for sloppily conflating the Higgs with the Inflaton on TV, which is certainly wrong, but the potential connection is well worth pondering.)

Steven Weinberg's book The First Three Minutes deals with the same subject, and its supposed to be really good.

The bottom line is the universe's baby pictures have a lot to tell us about the behavior of this quantum vacuum at much higher energies, which is where the big mysteries lie.

#sciencesunday﻿
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David is a great physicist and fantastic at explaining stuff. I am looking forward to watching the clip.

And yes, The First Three Minutes is a true classic. It's also got one of the great Weinberg downers of all time as an ending. You should read it!﻿
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### Cliff Harvey

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This saga about the BICEP measurement of the would-be primordial B-mode radiation continues to be highly fascinating. I noticed this write up by  that seems to do a pretty good job of explaining in general terms what’s happened recently as the BICEP and Planck experiments collaborate to compare their data, which he analogizes to two people with differently-colored sunglasses needing to communicate to infer the overall state of the sky.

Even the disappointing development of learning this signal can’t be unambiguously attributed to cosmic inflation has had some definite positive aspects in retrospect. It’s clearly the case that seemingly earth-shattering measurements often turn out to be wrong, for a variety of reasons, and watching it unfold is clearly conducive to developing the right kind of skepticism. It really has demonstrated why science simply works, when the right kind of substantive and careful criticism is brought to bear, as it was in this case. Beside this aspect, the initial surge of excitement around the possible signal compelled me to try to understand inflation in much more detail, especially how it generates the gravitational waves and the B-modes, and to learn about the challenges that confront attempts to make fundamental sense of inflation. So from my purely selfish considerations, this was a definite plus.

Of course it’s not just the positive signals that move science forward anyway, but excluding parameter space also gives tremendously valuable information. The limits from various experiments on the two main parameters characterizing inflation are illustrated at the chart in this post:

http://resonaances.blogspot.se/2015/02/weekend-plot-inflation15.html

It’s mentioned briefly on that blog, and its also been pointed out to me by , that one of the only inflationary models that sits right in the center of the preferred region is the Starobinsky model or R^2 model. This model is so named because instead of depending in the most straightforward way on R – the Ricci curvature scalar of general relativity – it adds a term proportional to R^2 to the fundamental equation (the Einstein-Hilbert action). There are a couple reasons this could be a very fascinating possibility from the standpoint of fundamental physics. For one thing, it can embed into supergravity and which reduces the required size of the initial homogeneous region by a couple orders of magnitude. For more on that I’ll refer you to his post and well-sourced wiki page:

http://ncatlab.org/nlab/show/Starobinsky+model+of+cosmic+inflation

It’s interesting to note in passing that this possibility, more generally called f(R) gravity, seems to be one of the very few ways that general relativity itself can be modified without instantly running into serious problems of one sort or another. I recall Nima Arkani-Hamed’s slogan “Don’t modify gravity, understand it,” which is particularly intriguing when you learn that R^2 gravity turns out to be physically equivalent to standard general relativity coupled to a new scalar field(!). It is this field that acts as the inflaton.

https://en.wikipedia.org/wiki/F(R)_gravity

It seems that no matter what new experimental signals turn up there will be many fascinating insights to uncover, and even if most of the models we focus on turn out to be wrong, if we get to better understand the space of consistent possibilities along the way, progress will still have been made.

#sciencesunday﻿
© Matt Strassler [February 6, 2015] Unfortunately, though to no one's surprise after seeing the data from the Planck satellite in the last few months, the BICEP2 experiment's claim of a discovery o...
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All experts I had talked to in person always just highlighted that Starobinsky is the best fit, but now there is debate about how much better it is than other fits. Table 6 in http://arxiv.org/abs/1502.02114 has the answer to this, but I am not sure if I know how to read it. I gather we are to look at the third and fourth column for the Bayesian relative likelihood (which is what is amplified in the text on the preceding pages). The notation "ln B_0X" seems not to be introduced in this article, though. Help me: what is the meaning of an entry "-k" in one of these columns? Is it: "the corresponding model is e^-k times as likely as the R^2 model?"﻿

### Cliff Harveyowner

Mathematics  -

From Veneziano to Riemann: A String Theory Statement of the Riemann Hypothesis
http://arxiv.org/abs/1501.01975
We discuss a precise relation between the Veneziano amplitude of string theory, rewritten in terms of ratios of the Riemann zeta function, and two elementary criteria for the Riemann hypothesis formulated in terms of integrals of the logarithm and the argument of the zeta function. We also discuss how the integral criterion based on the argument of the Riemann zeta function relates to the Li criterion for the Riemann hypothesis. We provide a new generalization of this integral criterion. Finally, we comment on the physical interpretation of our recasting of the Riemann hypothesis in terms of the Veneziano amplitude.
_____________________

Hilbert and Pólya independently suggested a physical realization of the Riemann hypothesis: if the zeroes of the zeta function in the critical strip are the eigenvalues of (1/2)I + iT and T is a Hermitian operator acting on some Hilbert space, then because the eigenvalues of T are real, the Riemann hypothesis follows. We do not know what the operator T is, nor what Hilbert space H it acts on. Nevertheless, the Hilbert-Pólya conjecture constitutes a tremendous insight into how a mathematics problem can be mapped to a physical system. Many recent works seek to establish such a connection explicitly.

In this note, we establish a physical realization of the Riemann hypothesis in terms of the properties of bosonic strings. In particular, we consider equivalent statements of the Riemann hypothesis written as integrals of the logarithm of the zeta function or the argument of the zeta function evaluated on the critical line. We link these expressions to the Veneziano amplitude describing the scattering of four bosonic open strings with tachyonic masses. This opens a fascinating new connection between string theory and the physics of the Riemann zeros. We also discuss the relation to the Li criterion for the Riemann hypothesis discussed in our previous publication, and we generalize the integral criterion based on the argument of the Riemann zeta function evaluated on the critical line.

In this opening section, we point out the fundamental reason why string theory, through the form of the Veneziano amplitude, should know about the Riemann zeta function, and thence about the Riemann hypothesis...﻿
Abstract: We discuss a precise relation between the Veneziano amplitude of string theory, rewritten in terms of ratios of the Riemann zeta function, and two elementary criteria for the Riemann hypothesis formulated in terms of integrals of the logarithm and the argument of the zeta function.
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thanks for always doing such a great job compiling these references. I still have a long way to go on grasping much of the information on nLab, but I am consistently impressed with it, and I definitely share the general sense of enthusiasm about the main concepts. Your participation here is always very much appreciated! ;)

There are many more things I've been meaning to post about in this community, including some of your own work, but I wanted to make sure I remembered to state this general sentiment.﻿

### Cliff Harvey

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For years I've waited for someone in the movie business to understand this one simple truth: no matter what fantastical stuff you might dream up for your sci-fi space flick, none of it will ever be more amazing or more provoking than what actually happens in real-life black holes. Well my wait is over. Chris Nolan and the people working on Interstellar have recruited Kip Thorne to help depict a black hole as it would actually appear, based on the equations of general relativity.

It looks stunning, and regardless of what the rest of the movie is like, seeing some of these world-class renderings of the black hole horizon and its accretion disk would practically be worth the ticket price on their own (but I've heard good things... fingers crossed ). As Kip says, studying the math of GR and black holes at any level has to leave you with some desire to see this kind of spectacle rendered as accurately as possible. (With the kinds of budgets these productions get away with, its almost a no-brainer to fund a mini research program for such a film.)

Apparently its been a productive collaboration even purely in terms of physics and computer graphics research, but I just have to see this imagery they've produced.﻿
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watch "The Black hole" Disney....it's cool﻿

### Cliff Harvey

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on organizing against institutional corruption
Its frustrating that for all the energy we see invested in political issues in the US, so far only a tiny fraction has been effectively focused on the central problem underlying essentially all of them: namely the system of private funding for public political campaigns. This would-be democratic republic is dominated by a transactional model of politics; a politics-by-auction. Numerical and anecdotal evidence of this situation is overwhelming, for example by the 93% correlation rate between winning the “money primary” and winning a House Congressional race. [1]

But this frustration is also what strikes me as precisely a cause for optimism, because it seems as though only a comparatively small fraction of the political energy that exists in the country would need to be refocused in order to actually make headway on the issue. The awareness seems much higher now. The signs of the problem are much more jarring and unavoidable. The understanding that campaign finance is a prerequisite for any other sane policies is increasingly obvious.

So I don’t think it is at all fantastical to talk about actually addressing this problem anymore. Some kind of public financing system would be the most direct solution, involving either small dollar donations amplified by public funds, or based on publicly funded “democracy vouchers” that citizens could give to candidates as they see fit. These kinds of reforms can be legislated, and they are the focus of Lessig and the RootStrikers, among other groups. Another class of approaches is the kind pursued by Wolf-PAC which is to press for Article V resolutions at the state level to amend the Constitution. This may be an important option to keep available, particularly given that the Supreme Court’s warped view of the first Amendment could lead them to strike down any public financing legislation as “unconstitutional limits on free speech”. (Sounds like something out of The Onion, I know, but it is exactly what the USSC did to Arizona’s public finance system in 2011.[2])

I don’t know which strategy will eventually be able to get the job done, but I do know that a large number of concerted efforts like these can build on each other. I know that collectively asserting awareness and determination is the first step towards attaining any such ambitious goals. And I now that failure would mean surrendering to an unacceptably bleak future.

So I strongly encourage following some of these organisations and getting involved in some way.

http://www.rootstrikers.org/
http://www.wolf-pac.com/
http://unitedrepublic.org/
https://represent.us/
http://unlimitedcorruption.com/

[1] https://www.opensecrets.org/news/2012/01/big-spender-always-wins.html
[2] http://en.wikipedia.org/wiki/McComish_v._Bennett﻿
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, have you seen any data that describes money in politics, but corrects for incumbency? Like, breaks things down into 'incumbent with more / less money' and 'challenger with more / less money' It seems like it could be a pretty significant data point. Like maybe we're looking at correlated facts that aren't causal.﻿

### Cliff Harvey

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Press conference on BICEP2, and other links
Heres the video of the press conference given this monday on the apparent detection of primordial gravitational waves by the BICEP2 experiment. As press conferences go its pretty solidly informative, with lots of details about the experiment but not so many that you get bogged down. It also has some interesting discussion about the theoretical aspects of inflation and with both major co-founders Alan Guth and Andrei Linde participating.

Needless to say, if its confirmed this an enormously important event, and I can't resist commenting on what seem to me like the most exciting implications. First its incredible to have what is really the first direct evidence of a quantum-gravitational process, and in particular a process driven by the mechanism of Hawking radiation. Both of these are things that seem nearly inevitable for any sensible theory of physics based on what we know today, but its still awesome to see them begin to move from the realm of well-grounded theoretical extrapolations into the realm of experimental science.

Even more exciting to me though are the hints by this measurement at grand unification, the possibility that the 3 non-gravitational forces may unify into one. It so happens that the just-measured energy scale of inflation corresponds to exactly the energy scale where the strengths of the 3 forces become about the same, at some 10^16 GeV, if you extrapolate them far beyond the energies that accelerators probe. This kind of of possibility has been the wet dream of particle theorists for many years. The hints towards such a scenario are indirect, but the fact that there is now one more indirect hint towards exactly the same energy scale is extremely tantalizing, and I feel more confident saying this now that some well respected theorists have concurred on this point. In the coming years, better measurements of the primordial B-modes will surely have something useful to say for building models of inflation, and I'd especially be on the lookout for models that can parsimoniously explain the dynamics of inflation together with some aspect of grand unification.

Now if anyone reading this still needs to get up to speed on the very basics of what's going on here, I think 's articles are perhaps some of the best if you're starting from very basic knowledge:

http://profmattstrassler.com/2014/03/17/a-primer-on-todays-events/
http://profmattstrassler.com/2014/03/18/if-its-holds-up-what-might-bicep2s-discovery-mean/

If you have a bit more of a head start on the basics, there is an awesome article by Liam McAllister on 's blog that very efficiently covers this measurement and its implications. In particular explaining what is the most interesting model-building constraint thrust on us by this data; the fact that the inflaton field has to be able to move by trans-Planckian amounts:

http://motls.blogspot.se/2014/03/bicep2-primordial-gravitational-waves.html

And here are a couple technical review articles I've read in preparation for this announcement. I'd welcome any other good suggestions:

http://arxiv.org/abs/1402.0526Inflationary Cosmology after Planck 2013
http://arxiv.org/abs/0907.5424TASI Lectures on Inflation

Finally, the last big message that I take away from this event is that nature doesn't give a damn if it's taxing on our intuition. Many commenters in recent years have expressed fervent opposition to inflation and other ideas because they don't like that it tends to produce other universes, and similarly misguided reasons. Many of these voices have failed to distinguish a proper scientific skepticism, which is to listen to nature and be weary of ideas that fly in the face of established physical principles, from a "skepticism" that is merely a general resistance to ideas that sound outlandish from a human's intuition. Its certainly not a bad thing to propose a model that turns out to be wrong, but some of the models of the early universe that have just been falsified were motivated by exactly these sorts of feelings. With respect to those cases, this finding seems like one more indication from the universe that these attitudes may not be a useful guide to understanding how things work fundamentally.

To quote Liam McAllister, we learned this week that "the tensor fluctuations write quantum gravity on the sky," and that is definitely something worth celebrating.﻿
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I love high energy physics, computer science and giant robots
Introduction
Above all, Im passionate about physics. More generally Im interested in furthering understanding of this world at all levels, from particle physics to economics to galactic superclusters and everything in between. I have an artistic side I once cultivated aggressively but has somewhat fallen by the wayside. My inner artist/musician is howling to get let out soon.

As a physics major at WPI, I did a couple major research projects on quantum information theory, specifically on proofs of Bell's theorem involving 4 and 5 qubits. Those projects heavily shaped the way I view physics in general, and its deep foundational issues in particular. Despite the difficulty of the subject, I am convinced there is much more confusion than is necessary, as sloppy reasoning and explanations persist.

At the moment Im mostly spending my time learning quantum field theory and string theory. I am consistently amazed by the unity of physical and mathematical logic, and as I've studied the structure of this logic I've inexorably gravitated to the stringy school of thought. Despite the challenges, it seems to me an essentially indispensable set of puzzle pieces that allow the whole structure to make sense. It appears so deeply enmeshed that extrication just does not seem very likely. But, as a scientist, I of course try to challenge any presumptions of mine aggressively.

Ill forever be a theorist at heart, but I also want to find a rewarding way to use my skills for something more down to earth. I think becoming a better computer scientists may be one of the better ways for this to happen.

And I believe that those of us awake to the challenges facing the human race – especially intellectuals, anyone who analyzes things systematically – has a certain obligation to actively stand for the truth and what is right. As a US citizen Im especially focused on the issue of campaign finance as fundamental to all other political problems in the US.

"There are a thousand hacking at the branches of evil to one who is striking at the root."

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