Here's a question that's been on my mind for quite some time now.
What the actual hell is energy?
Like, seriously. I understand real-life is nothing like fiction where characters and machines can shape energy into tangible spheres, beams and various other forms, but I honestly can't take the notion that energy is merely a property of a physical system seriously anymore given everything I've learnt about it.
Ok, ok... first of all, energy can change forms... no, hold on... energy can EXIST in multiple forms. Light, thermal, kinetic, sound/vibrational, electromagnetic/radiant, etc. The ability to change forms, you know, TRANSFORM feels like something a physical thing that doesn't just exist as a property of a system has the ability to do. Hell, matter has the ability to do just that, and matter, like it or not, is an actual thing that we can define and see.
Speaking of seeing things, light. It's something we can see with our eyes (like matter) and it can exist in the form of a particle called a photon, and let me tell you these little buggers can do some pretty crazy stuff. What kind of crazy stuff though? Well laser beams (which are made of photons of light) have the ability to defect matter to the point that it either ruptures, ignites or both, and objects such as crystals and mirrors have the ability to reflect those beams in the opposite direction they were pointed at. Even crazier than this however is a photon's ability to move, like, actually straight up apply motion to matter by transferring their momentum to them.
Let me repeat that. Photons, which are LITERALLY made of energy and have no mass whatsoever, have the ability to apply force to physical objects and cause them to move. Solar sails use the momentum from the Sun's rays to achieve a speed of 18,600 miles per second (or 67,100,000 mph if you wanna get technical). Yes, the amount of energy we're dealing with here is unreasonable by the standards of our planet's various nuclear plants and wind turbines, but the point still stands. Light shouldn't be able to move anything like this unless light itself was also a 'thing'.
And finally, just to top it all off we have Einstein's famous E = MC² equation, which gave rise to the notion that matter (or I guess mass in this case) and energy were one and the same and could be transformed into each other. Now, we already have tons of examples of this formula working in one direction in the form of combustion, nuclear explosions, nuclear fission and nuclear fusion, but we've also seen scientists achieve the opposite affect and turn energy in the form of photons into matter and antimatter particles via a particle collider. The Big Bang also created matter out of energy, and we even have evidence of this in the form of the Cosmic Microwave Background.
So energy can exist in multiple forms, physically interact with matter as if it were something tangible, can be turned directly into matter and vice-versa and some forms of energy like light, sound and heat can be perceived by the naked eye (ok, that's a lie. Only light can actually be visibly seen by the human eye, the other two require special technology). If energy really can't be considered a 'thing' the same way that matter is often considered a 'thing', why does it have any of these properties? Why can I clearly feel and see its effects on the world around me? What actually is energy?