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Latest posts from the archive.

My Life: A Personal Account (Part 2)

This is the second in a series of posts detailing my personal battle against depression from the early teenage years uptil the present day. The first post can be found here.

The “Rediscovery” of Spin Networks and Loop Quantum Gravity

Its hard to describe the frustration and anger I feel to see all these papers talk about “tensor networks” and geometry as if they are discovering something new which wasn’t…

Battling Depression: A Personal Account (Part 1)

Depression is a terrible disease. What amplifies its debilitating effect is its invisibility. There are no physical symptoms apparent to the external observer. In the…

Criteria for a Theory of Quantum Gravity

In an upcoming blog post I will outline a proposal theory of quantum gravity based upon the positive Grassmannian based upon my work with my student Devadarshini Suresh. It…

Complexity and Classicality

Earlier this summer I had the good fortune to be able to attend an (online) workshop on information and complexity. One of the most fascinating talks was by Scott Aaronson…

``Loop Quantum Gravity is Dead … ’’

... is a phrase that many high energy theorists, especially those of the stringy persuasion, long to hear. Fortunately, to borrow a phrase from Mark Twain, reports of the…

This Year-ish in Theoretical Physics

The previous episode of “this week-ish” was posted on June 5. Its been six months since then. I guess its time to post another volume but to be fair the title of this post…

Specific Heats of AdS Black Holes and Quantum Geometry

In (Johnson 2020), Clifford Johnson makes yet another contribution to the study of black holes in anti-deSitter spacetimes or AdS black holes, for short. In this work he…

This Week-ish in Theoretical Physics

Surely it is hubris on my part to presume to co-opt the title of the venerable online column “This Week’s Finds in Mathematical Physics” written for nearly seventeen years…

Implementing Quaternions in Julia

Julia is making waves in the scientific programming community as the language to learn if you truly want to be a computational code ninja. I won’t list out all the features…

On the Compactness of Anti-deSitter Space

In my last post, on the IAGRG30 Conference held at BITS Hyderabad, I had mentioned how during my talk I was corrected by Amitabh Virmani on a seemingly technical point. My…

IAGRG30 - Kepler, Maldacena, Ashtekar and all that …

I was recently in BITS Hyderabad ¹ attending the 30^th meeting of the Indian Association for General Relativity and Gravitation (IAGRG30). I was pleasantly surprised that my…

Comment on "A Post-Quantum Theory of Classical Gravity"

Sometime ago Jonathan Oppenheim, one of the brightest minds (Michal Horodecki, Oppenheim, and Winter 2005; Oppenheim 2010; Oppenheim and Wehner 2010; Michał Horodecki and…

Cosmological Curvature and the Planck Scale

While reading up on anti-deSitter spaces in (Bengtsson 2008), I encountered the following quote attributed to Gauss by the author:

DAE-HEP 2018 - Preons, Fermions and All That

The 23^th DAE-BRNS High Energy Physics Symposium was held at IIT Madras from Dec 10 - Dec 14. It was an interesting event. I met lots of very smart people. My abstract based…

Zotero vs Mendeley

There are two nice reference management apps out there with desktop and web versions: Mendeley and Zotero. Zotero is apparently the original open source version from which…

Shoucheng Zhang, 1963-2018

I never had the good fortune of meeting or personally knowing Shoucheng Zhang. Nevertheless he has had a profound influence on my academic career. As the world learned…

Negative Temperatures

The thermodynamic concept of temperature is defined by the following equation: \(T = \frac{\partial E}{\partial S}\)where\(E\)is the energy of the system and\(S\)is the…

Social Relevance of Quantum Gravity

Other ¹ than all the other very good theoretical reasons for wanting a theory of quantum gravity, there are some very good practical reasons for wanting such a theory.…

The Planck Scale May Be Closer Than It Appears

Objects in the rearview mirror may be closer than they seem.

Euler's Homogenous Function Theorem

A homogenous function of order \(n\)satisfies:\(\nf(\lambda x_1, \lambda x_2, \ldots, \lambda x_m) =\lambda^n f(x_1, x_2, \ldots, x_m)\n\)For e.g.\(\nf(x,y) = \sqrt{x} y^2\n\)…

Euler's Theorem and the Smarr Relation

The area of a charged rotating (Kerr) black hole is given by

Plugins for Migrating Wordpress Installations

For anybody who manages a wordpress installation, a question that inevitably arises at some point or another is how to migrate their site from one hosting provider to…

How to kill a great platform

There are few things in life more disappointing than watching a beautifully crafted, socially responsible, disruptive technology platform self-destruct from the inside out.…

EVONET18 - Tensor Networks for One and All

So one month ago there was this wonderful workshop on “Optimising, Renormalising, Evolving and Quantising Tensor Networks” - or EVONET18 - organized by the Max Planck…

An Epidemic in India

A disease has spread throughout this great land of ours. To be sure, this disease is not new to us Indians. In some ways it has become part of our very national DNA. It has…

Theoretical Physicists in India

There are many research centers and researchers in India working in hep-th (High Energy Physics, Theory), gr-qc (General Relativity/Quantum Cosmology) and quant-ph (Quantum…

Competitive Nationalism and (the myth of) Islamic Homogeneity

Recently the Chief Minister of Karnataka, Mr. Siddharamaiah, made the following observation on twitter regarding the recent communally motivated murders in the Dakshin…

Herniated Disc Exercises

Found a really nice set of five simple exercises for treating herniated or bulging discs. The exercises are:

Fluctuation Dissipation in Quantum Gravity

In statistical mechanics we are mostly concerned with the statistical averages of various physical quantities when the system is in equilibrium. Fluctuation is a common…

Speeding up Wordpress

One common problem with wordpress sites is that they can seem sluggish compared to, lets say, sites built with static or single-file CMSs such as grav. There are several…

Spacetime Geometry as Information Geometry

In an entry to the 2013 FQXi essay contest and in an accompanying paper, Jonathan Heckman, a postdoc at Harvard, put forward a scintillating new idea - that one can derive…

Transcending Bad Sci-Fi

So I was watching “Transcendence”, the latest cinematic attempt to generate public hysteria about Artificial Intelligence (AI), or more specifically about Hard AI. I stopped…

Multiverse, multiverse, where art thou?

As I understand it, the multiverse concept arises as a consequence of the standard inflationary scenario which involves one or more scalar fields “rolling down” the side of…

The Measurement Problem, Part 1

The measurement problem becomes a problem only when we neglect to specify the nature of the observer’s Hilbert space. Postulates I (Systems are described by vectors in a…

Thermal Time and Kepler's Second Law

In a fascinating recent paper (arXiv:1302.0724), Haggard and Rovelli (HR) discuss the relationship between the concept of thermal time, the Tolman-Ehrenfest effect and the…

Some things … cannot be learned quickly

There are some things which cannot be learned quickly, and time, which is all we have, must be paid heavily for their acquiring. They are the very simplest things, and…

Elementary particles and quantum geometry

Black holes are formed due to the gravitational collapse of matter - ordinary matter, consisting of the particles and excitations of the Standard Model that we know and…

… and so it begins

Welcome to my blog, gentle readers. Here you will be exposed to all manner of speculation and conjecture on my part. Those with an enhanced sensitivity to non-rigorous…