The light at the end of the tunnel? A study unravels what happens when life goes dark.

Perhaps one of the greatest mysteries in existence is what happens when life ends. That moment, which some describe as "the light at the end of the tunnel," has remained a mystery that has been explored from multiple angles.

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The question may have an answer thanks to a study published in the Journal of Physical Chemistry Letters.

The first thing to keep in mind is that it has been known for years that all living beings emit extremely faint light radiation, imperceptible to the human eye, called very weak photon emission. This "light" fades just as life comes to an end.

The novelty lies in the fact that, thanks to the use of ultra-delicate digital cameras, this phenomenon has been observed at a level of detail never before seen. The result reveals that once vital functions cease, this mysterious inner light also goes out.

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This glow is produced by something known as biophotons, light particles spontaneously generated by cells. Their intensity ranges from just 10 to 1,000 photons per square centimeter per second , making them invisible to the human eye.

To conduct this experiment, the researchers were careful to maintain constant temperature conditions to avoid interference and compared the photon emission of live and dead mice.

Thus, they were able to capture the exact moment when the emission of this 'light' ceases, coinciding with biological death.

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