Source: New Scientist

Despite significant advancements in physics, several fundamental questions remain unresolved.

These mysterious components make up about 95% of the universe, yet their exact nature remains unknown. Dark matter is inferred from gravitational effects on visible matter, while dark energy is hypothesised to be driving the accelerated expansion of the universe.

The universe appears to be composed predominantly of matter rather than an equal mixture of matter and antimatter. The mechanisms leading to this imbalance are not fully understood.

The Big Bang theory describes the evolution of the universe from a very early stage, but the actual origin of the universe, the conditions at the singularity, and what (if anything) came before it remains open questions.

How and why conscious experiences arise from physical processes in the brain is a profound mystery. This is a major interdisciplinary question involving physics, neuroscience, and philosophy.

How information about the material that falls into a black hole is preserved and whether it can be retrieved after the black hole evaporates via Hawking radiation remains a debated issue.

The fundamental nature of time, including why it seems to flow in one direction (the arrow of time), is not fully understood. This ties into thermodynamics, cosmology, and quantum mechanics.