Something Deeply Hidden - Sean Carroll[1]

Lost in Math - Sabine Hossenfelder[2]

The First Three Minutes - Steven Weinberg[3]

Hyperspace - Michio Kaku[4]

Not Even Wrong - Peter Woit[5]

The Trouble With Physics - Lee Smolin[6]

About Time - Paul Davies[7]

Time Reborn - Lee Smolin[8]

The Elegant Universe - Brian Greene[9]

The Hidden Reality - Brian Greene[10]

The Fabric of the Cosmos - Brian Greene[11]

Quantum Space: Loop Quantum Gravity and the Search for the Structure of Space, Time, and the Universe - Jim Baggott[12]

The Universe Speaks in Numbers: How Modern Math Reveals Nature's Deepest Secrets - Graham Farmelo[13]

Three Roads To Quantum Gravity - Lee Smolin[14]

Programming the Universe: A Quantum Computer Scientist Takes on the Cosmos - Seth Lloyd[15]

Higgs - The invention and discovery of the 'God Particle' - Jim Baggott[16]

[1]: https://www.amazon.com/Something-Deeply-Hidden-Emergence-Spa...

[2]: https://www.amazon.com/Lost-Math-Beauty-Physics-Astray/dp/15...

[3]: https://www.amazon.com/First-Three-Minutes-Modern-Universe/d...

[4]: https://www.amazon.com/Hyperspace-Scientific-Parallel-Univer...

[5]: https://www.amazon.com/Not-Even-Wrong-Failure-Physical/dp/04...

[6]: https://www.amazon.com/Trouble-Physics-String-Theory-Science...

[7]: https://www.amazon.com/About-Time-Einsteins-Unfinished-Revol...

[8]: https://www.amazon.com/Time-Reborn-Lee-Smolin/dp/0544245598/

[9]: https://www.amazon.com/Elegant-Universe-Superstrings-Dimensi...

[10]: https://www.amazon.com/Hidden-Reality-Parallel-Universes-Cos...

[11]: https://www.amazon.com/gp/product/0375412883/ref=dbs_a_def_r...

[12]: https://www.amazon.com/Quantum-Space-Gravity-Structure-Unive...

[13]: https://www.amazon.com/Universe-Speaks-Numbers-Reveals-Natur...

[14]: https://www.amazon.com/Three-Roads-Quantum-Gravity-Smolin/dp...

[15]: https://www.amazon.com/Programming-Universe-Quantum-Computer...

[16]: https://www.amazon.com/Higgs-invention-discovery-God-Particl...

Could be just this line: "‘loop quantum gravity’ — a theoretical attempt that has yet to find experimental support"

As @jerf points out here as well, LCG has as much experimental support as any of the other competing GUT hypotheses... which is to say, none. This whole "thing" about the lack of experimental support and lack of testable / falsifiable assertions in physics (especially String Theory) is explored at length in two pretty interesting books: Not Even Wrong[1] by Peter Woit and The Trouble With Physics[2] by Lee Smolin.

[1]: http://www.amazon.com/Not-Even-Wrong-Failure-Physical/dp/046...

[2]: http://www.amazon.com/The-Trouble-With-Physics-Science/dp/06...

You may not be so "out there" at all. There were two books that came out a few years ago, both basically lambasting the state of physics - especially string theory. One was titled Not Even Wrong[1] and the other was titled The Trouble With Physics[2]. As best as I can tell, of the two (and I'm afraid I can't remember which it was now) made the case that we might be completely wrong about the nature of time. The idea was that the reason we have had to resort to such (seemingly) byzantine theories as string theory, without seeming to make much progress on deciding which string theory is correct (or if it's correct at all) is tied up in this misunderstanding of time. IOW, before we make any really fundamental breakthroughs in physics, we will have to re-conceptualize time itself.

Now that's a pretty bold claim, and I have no idea if it is correct or not. But it's a position held by at least one fairly well known and reputable physicist.

[1]: http://www.amazon.com/gp/product/0465092756

[2]: http://www.amazon.com/The-Trouble-With-Physics-Science/dp/06...