Quantum Physics Explained | Technical Prabhuji

The world we see around us functions according to certain laws of physics. The rising and setting of the sun, the change of seasons, a train continuing to move a bit after the brakes are applied, a ball landing at a particular spot depending on the angle and speed it's thrown, lack of mobile network in some areas, a medicine relieving a headache after being digested, or an airplane landing safely on the ground—all these happen due to certain physical laws. These include the law of gravitation, the law of conservation of energy, the law of conservation of momentum, Newton’s laws of motion, and the laws of thermodynamics. All of these come under what we call classical physics, and everything in our daily world operates under these classical laws. 

But the tiny particles that make up this world—like quarks, photons, electrons, protons, and neutrons—do not follow the rules of classical physics. Classical physics breaks down at the atomic level. The laws that work at the cosmic level don’t apply at the quantum level. This realization led to the birth of quantum physics or quantum mechanics. 

Quantum physics is the most mysterious branch of modern science. Renowned physicist Richard Feynman, who won the Nobel Prize for his work on Quantum Electrodynamics, once said, “If you think you understand quantum physics, then you don’t understand quantum physics.” That’s how strange it is. 

The first and most fundamental discovery in quantum physics, upon which the whole field is built, is wave-particle duality. To understand that, let’s first understand what a wave and a particle are. A wave is simply a disturbance that travels through space or matter and transfers energy—for example, sound waves, water waves, or radio waves. A particle, on the other hand, is a physical object with mass. 

In 1704, Sir Isaac Newton published a book titled Opticks, in which he proposed the corpuscular theory of light—suggesting that light is made of tiny particles called corpuscles. 

About a hundred years later, in 1801, scientist Thomas Young performed a landmark experiment known as the Double Slit Experiment. He passed light through two slits in an opaque plate and observed the resulting pattern on a screen placed behind it. Instead of getting just two bright spots (as expected if light were made of particles), he saw an interference pattern, just like waves create when they overlap. This showed that light behaves like a wave. Many other scientists repeated this experiment and confirmed the same result—light is not a particle but a wave. 

However, in 1905, Albert Einstein explained the photoelectric effect in a research paper for which he later received a Nobel Prize. He showed that light is made up of tiny energy packets called photons. When light hits a metal surface, these photons transfer their energy to electrons, causing the electrons to get ejected from the surface. This couldn’t be explained if light were only a wave. Einstein proposed that light behaves both as a particle and as a wave. This concept, called wave-particle duality, became one of the most revolutionary ideas of modern science and the foundation of quantum mechanics. 

Later, the scientific world was truly shocked when physicist Claus Jonsson in 1961 repeated the Double Slit Experiment, but this time using electrons instead of light. He fired single electrons one by one through the slits and placed an electron-sensitive screen on the other side. Surprisingly, the electrons didn’t just form two spots but created a wave interference pattern, just like light did. 

This proved that not just light, but every quantum entity—be it photons, electrons, protons, or neutrons—exhibits both wave-like and particle-like behavior. In other words, all the fundamental building blocks of the universe act both as waves and as particles. This is something that’s simply not possible in the classical world. For example, in our everyday world, a table is a solid object; it’s not a subtle vibration. But at the quantum level, that table is just made up of vibrations. Until we observe or measure it, there are no solid particles in it—this is a scientifically proven fact. 

And here’s the most mysterious part: when scientists placed an observer device near the slits to watch the electrons as they passed through, the interference pattern disappeared. The electrons suddenly started behaving like particles, hitting just two spots on the screen. But without the observer, they behaved like waves and created an interference pattern. This is known as the observer effect. At the quantum level, particles behave like waves until they are observed—then they behave like particles. 

Because of this, quantum physicists say that the world around us is not fixed or solid until we observe it. When unobserved, reality is one thing (let’s call it X), and when observed, it becomes something else (Y). In other words, the very act of observation changes reality. 

So, based on these two discoveries—wave-particle duality and the observer effect—quantum physics concludes that the entire universe at its most fundamental level is just energy waves. Only when an observer interacts with it does it take a specific, measurable form. 

Interestingly, what modern science has taken 300 years to discover is beautifully captured in just three Sanskrit words from the Chandogya Upanishad: 
"Sarvam Khalv Idam Brahman"—everything that exists is Brahman. 

And what is Brahman? It is described as a combination of three energies: Samvit (consciousness), Sandhini (existence), and Hladini (bliss). Vedic scriptures like the Rig Veda, Yajur Veda, Shvetashvatara Upanishad, and Brahma Samhita declare that sound is the foundation of creation. For instance, the Srimad Bhagavatam 3.26.32 says: 
"Shabda-mātram abhūt tasmat nabhah" – Meaning that at the beginning of creation, sound (shabda) activated Brahman and created space, and from space, all other elements started forming. 

Similarly, the Mandukya Upanishad begins with: 
"Harih Om. Om iti etad aksharam idam sarvam" – The entire existence is made from the sound of “Om,” which is the transcendental sound of Bhagavan Hari. And what is sound? It’s a wave. So, modern science also agrees that at the quantum level, everything is made of waves. And we, as souls, are the observers of this existence. 

In the Bhagavad Gita, Chapter 14, last verse, Lord Krishna says: 
"Brahmano hi pratishthaham amritasya avyayasya" – “I am the foundation of Brahman, which is immortal, imperishable, and eternal.” 
And in Chapter 15, Verse 7, Krishna says: 
"Mamaivamsho jiva loke jiva bhutah sanatanah" – “All living beings in this world are My eternal parts.” 

This means that beyond Brahman and the individual soul (jiva), there is a third eternal entity—Bhagavan, or the Supreme Lord, Sri Krishna. Of the three eternal entities—Brahman (energy), Jiva (soul), and Bhagavan (God)—the first two are subordinate to the third. 

Scripture says that unless the soul recognizes this relationship with God and lives in that connection, it will continue to take birth after birth in this temporary world, going through cycles of happiness and sorrow based on its karma and desires. The soul keeps taking different bodies. 

But when the soul lives in loving service to God and understands its relationship with Him, then even in this temporary world, it can experience deep spiritual bliss. And at the end of such a life, it becomes free from the cycle of birth and death and enters the spiritual world—the eternal abode of Lord Krishna. 

This entrance into the spiritual world and a life of loving service to Krishna is the highest perfection that the soul can achieve.