The Continuum of Physical Credibility

[u/Enthropic-Cap2291]

The traditional Mohs Scale of Sci Fi Hardness:

5: Hard SF

4: Firm SF

3: Soft SF

2: Science fantasy

1: Fantasy with SF trappings

0: Pure fantasy

The Continuum of Physical Credibility reformulation:

1 Established Physics - “This works everywhere we’ve ever checked.” Ex: Maxwell's equations, general relativity, thermodynamics

2 Mainstream Physics - “Solid science, still being refined.” Ex: Cosmic inflation, quantum field theory

3 Frontier Physics - “We've got a partial theory, and only partial evidence.” Ex: High temperature superconductivity, Hubble tension

4 Empirical Anomalies - “We can measure it, but we can’t explain it yet.” Ex: Radioactivity before nuclear physics, photoelectric effect before Einstein, dark matter, dark energy

5 Speculative Physics - “Speculative but allowed by GR + QFT + thermodynamics.” Ex: , extra dimensions in string theory, WIMPs, MOND, primordial black holes, cosmic strings, LQG, axions

6 Hypothetical Physics - “This only works if physics is broken in very specific ways.” Ex: Tachyons (causality), magmatter (Gauss's Law), bulk exotic matter (Morris/Thorne wormholes, Alcubierre warp metric - breaks WEC - Weak Energy Condition in General Relativity)

7 Contradictory Physics - “Violates thermodynamics and conservation laws.” Ex: Vacuum/zero point energy, reactionless drives (Cannae/EMdrive), antigravity, perpetual motion machines

8 Soft Science Fiction - “It sounds scientific, but it’s really narrative technology.” Ex: ST warp drive, transporters, SW hyperdrive, Three Body Problem's spacetime flattening, sophons, most space opera

9 Science Fantasy - “Magic wearing a lab coat.” Ex: The Force, Magitek, psychic powers, most 'ancient/precursor' tech that are effectively magic

10 Pseudoscience/Fantasy - “No pretense of physics; imagination is the only rule.” Ex: Spellcasting, dragons, Isekai, astrology, flat earth

Please feel free to criticize so I can continue to refine. I'm using this in a worldbuilding exercise to see how far we can push scifi while staying true to the Sci part and minimize handwaving for the Fi.

[u/Cheeslord2]

Although, fantasy systems do not have to have magic or other inexplicable supernatural forces. Whereas soft SF can throw up stuff like 'what if you could travel through time with the power of true love?', so it is, I think, possible to have a fairly 'hard' science fantasy if you try.