iiinova — where your digital self keeps evolving

The notes are aimed at advanced undergraduate and beginning graduate students, and even the sophisticated layman. Hope you find them useful!

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... to here, all in a compact, self-contained series of lectures.

I cover the Twin Paradox, and the Ladder/barn Paradox, as well as accelerated reference frames, the Bell Rocket Problem, and even the Rindler Horizon, all in Special Relativity.

From this viewpoint, the "paradoxes" in Special Relativity boil down to simple problems in hyperbolic trigonometry, and spacetime diagrams make everything clear and intuitive

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Instead of starting with rods, and clocks on trains, I go straight to the invariance of the inner product on Minkowski space, and develop SR with the rapidity as the fundamental variable.

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As a result, I have found that even graduate students are poorly prepared in basic relativity theory. So I put together a set of lectures to fill in the gaps, and show them SR as a geometric theory.

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Students in modern physics programs are often taught SR as mostly an afterthought in required E&M classes. Even in elective "Modern Physics" classes, it is taught in an old-fashioned, often very confusing way.

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It arose out of a need to get students up to speed on SR as an intro unit in Cosmology and General Relativity classes.

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Boot Camp is a set of lecture notes suitable for a short, intensive introduction to Einstein's Special Theory of Relativity seen from a geometric viewpoint.

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Since the preprint version seems to on indefinite hold at arXiv, I'm pleased to share the web version of Special Relativity Boot Camp. www.acsu.buffalo.edu/~whkinney/Sp...

Will Kinney @wkcosmo.bsky.social · 27/07/2026

The good news is, I have set up a web page with errata for "Inflationary Cosmology." The bad news is, there are now two entries. www.acsu.buffalo.edu/~whkinney/In...

acsu.buffalo.edu

Errata — Inflationary Cosmology

Errata for Inflationary Cosmology

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Will Kinney @wkcosmo.bsky.social · 27/07/2026

Errata for Inflationary Cosmology may be found here. I will update as necessary. www.acsu.buffalo.edu/~whkinney/In...

acsu.buffalo.edu

Errata — Inflationary Cosmology

Errata for Inflationary Cosmology

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Will Kinney @wkcosmo.bsky.social · 19/06/2026

"Inflationary Cosmology" is now in stock at Amazon! www.amazon.com/Inflationary...

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Will Kinney @wkcosmo.bsky.social · 05/06/2026

Order here: www.worldscientific.com/worldscibook...

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Will Kinney @wkcosmo.bsky.social · 05/06/2026

The new book has been printed! Sample chapters: www.worldscientific.com/doi/suppl/10... www.worldscientific.com/doi/epdf/10....

Will Kinney @wkcosmo.bsky.social · 26/02/2026

Yeah they could work on their AI a little. 😆

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Will Kinney @wkcosmo.bsky.social · 26/02/2026

20% off pre-orders of my new book, Inflationary Cosmology. www.worldscientific.com/worldscibook...

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Anyone who is serious about understanding the theory of inflation at a deep level should own both. I hope you enjoy.

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https://www.worldscientific.com/worldscibooks/10.1142/14698#t=aboutBook

You can pre-order Cosmological Inflation from World Scientific at this link: t.co/JHoTxMKsRh

t.co

This is an advanced textbook, suitable for graduate students and postdocs with a basic knowledge of General Relativity and Quantum Field Theory.

I cover modern topics such as eternal inflation, DBI models, ultra-slow-roll inflation and the Borde-Guth-Vilenkin Theorem, and the Trodden-Vachaspati Theorem.

I discuss the state of the art in constraining theories of inflation by observation.

I cover General Relativistic perturbation theory in detail, from first principles, and semiclassical quantization of fields in curved spactime, for both canonical and non-canonical field theories.

Everything I discuss at a qualitative level in An Infinity of Worlds, I revisit with full mathematical rigor in Cosmological Inflation.

If you read my first book and found yourself wishing it had more math, here you go: where An Infinity of Worlds focuses on the structure and philosophy of the theory, Inflationary Cosmology fills in all the mathematical details.

My new book Inflationary Cosmology is like Weinberg's appendix: a mathematical companion to An Infinity of Worlds.

Weinberg's book was unusual for a pop science book, because it included a technical appendix, which actually went into the mathematical equations governing the Big Bang.

What we call the Big Bang is now understood as the END of the process of cosmic inflation, in which our universe is but one of infinitely many being continuously generated out of the quantum vacuum.

It was inspired by Steven Weinberg's classic, "The First Three Minutes", which was published in 1977. Our understanding of the beginning of everything has deepened immensely since then.