## About

I am a researcher in quantum information theory based at the Institut für Theoretische Physik, Leibniz Universität Hannover. I am interested in quantum information theory and complex quantum systems.

Inspired by the recent discussions (see, eg., Michael Nielsen’s blog postings) surrounding open science I decided to start a weblog containing my research notes. I intend to post my notes on my various research projects along with some expository material. It is my hope that this weblog can become a forum for open discussion and research. Thus I would like to invite you to *comment*, *contribute*, and *collaborate!* If you make any progress on the ideas or open problems discussed on this site then please let me know via the comments: I am more than happy for anything here to become a joint project, the more the merrier!

### Like this:

Like Loading...

Our website Science.org is a informational databases and online news publication for anything and everything related to science and technology. We recently ran a poll asking our website users regarding what online informational resources they use to keep up to date or even to simply find great information. It seems many of our users have labeled your blog as an excellent source of Space information. We have reviewed your blog and must say, we absolutely love the information you have made available to the public and would love to make your blog a part of our top science blogs. After browsing your blog, our research team has decided to award you a Top science Blogs award banner.

I like your blog. I am really in to math even though I am only 14 and Maybe one day I will discover new things like you are doing. :).

Does that mean you’re just 22/23 right now and you’re already a professor? :O

Hello Sir

i am a phd student working in condesed matter physics

i thank you for the sharing your lecture notes on variational principles in quantum mechanics.

they proved to be very helpful in understanding many things .

particularly they helped to get a better understanding of DMRG.

i would like to know whether renormalization procedure itself can be thought in terms of variational principle?

best regards

rukhsan

ps can i have your mail id!

Dear rukhsan,

Many thanks for your email and your interest!

To answer your question: “i would like to know whether renormalization procedure itself can be thought in terms of variational principle?”

I think the answer is not clear at the moment: some RG schemes are like variational principles, but, e.g., Wilson’s original momentum space RG is not obviously connected. So there is still work to do to find a connection…

Sincerely,

Tobias

Hello,

Are you still working on those open science projects on GitHub?

Thank you.

Dear John,

Many thanks for your question: indeed we are still working on these projects. There will be imminent changes soon as we begin to work on a final paper for each of the projects.

Sincerely,

Tobias

Dear Professor,

could it be or am i entitled to mention my impression,

that you used the words “criteria” and “momenta” as if they would be the singular form of / instead of “criterium” and “momentum” during Advanced QM YouTube Lectures seemingly preferrring the feminine form (Femininum) over the Neutrum (deutsch) allthough they are the Mehrzahl…………….?

Greetz RWitold

Dear Tobias,

Would you be open to discuss over this blog a VERY BASIC point about the General Theory of Relativity? In my opinion. a re-think on this basic point opens up a big new window on Physics.

Please do let me know.

With best wishes,

Naresh

[PS: My blog is on another subject altogether — not Physics]

Dear Sir and folks,

I am interested in applying ideas from statistical mechanics and symplectic geometry in optimization theory to derive general continuous-time algorithms (i.e. ODEs/SDEs) that may represent a broader class of already existing discrete-time algorithms.

Due to prevalent rigorous theory of differential equations both in deterministic (ODE) and stochastic (SDE) setting our analysis will be much more general, insightful (we will be able to provide answers to questions like: why optimization algorithms can be accelerated by adding momentum and what does adaptivity translates to, in continuous time) and of course elegant.

For discretization of these algorithms (so that they can be implemented practically) symplectic integrators could be used because of the following result: “conformal symplectic integrators can preserve convergence rates of the continuous system up to a negligible error.” An intriguing study on these ideas is done in https://arxiv.org/pdf/1903.04100.pdf

This is just the beginning of the field of symplectic optimization (https://arxiv.org/pdf/1802.03653.pdf) and there are lots of open questions to be answered. So, it would be amazing to collaborate in these directions if anybody is interested.

A little bit about me: I’m a beginner in symplectic geometry and have been following sir’s lectures and an intermediate in optimization theory. We can learn together if somebody is interested in these directions :). Kindly let me know.

Cheers,

Navish

PS. Sir I would be grateful if you could let me know your thoughts on this. Thanks!