<< Rome, Italy,JUN 28 2024 >> NOTE: This is a first cut to get to press. This subject is so complicated that it may take a few updates to get this article correct. Quantum entanglement is a fundamental phenomenon in quantum mechanics where two or more particles become linked in such a way that the state ofone particle is directly related to the state of the other, no matter how far apart they are. This means that if you measure the state of one particle, you immediately know the state of the other, even if they are millions of miles apart. This correlation between particles persists regardless of the distance between them, a phenomenon that Albert Einstein famously referred to as "spooky action at a distance". As mentioned earlier, Einstein may have discovered QM, but he was never comfortable with it. At the core of entanglement is the concept that quantum particles, like electrons or photons, don't have definite states until they are measured. As we learned earlier, they exist in a superposition, which means they can simultaneously be in multiple states. When two particles are entangled, their properties, such as spin or polarization, become interdependent. If one particle is measured and ("wave") collapses into a particular state, the entangled partner instantly collapses into a corresponding state, even though no signal has traveled between them. So superposition and entanglement are interrelated. The odd nature of quantum entanglement challenges standard concepts about how objects should behave. In classical physics, objects have properties that are independent of observation, and no influence can travel faster than the speed of light. Quantum entanglement defies these notions, suggesting that entangled particles somehow share information in a way that is not bound by space and time. This seemingly impossible phenomenon has been at the center of intense debate and experimental investigation. To this day we dont understand why this works. Quantum entanglement has practical uses for emerging technologies, especially in the field of quantumcomputing and quantum cryptography. In quantum computing, entangled qubits can perform complex operations more efficiently than classical bits by simultaneously representing multiple possibilities. Quantum cryptography, uses entanglement to create secure communication channels that cannot be eavesdropped on without disturbing the system, as any measurement would disrupt the entanglement. We will look at both of these tecnologies in future articles. Entanglement has been repeatedly observed and proven to exist in laboratories through tests like Bell's theorem, which provides a way to test the predictions of quantum mechanics against classical physics. The experimental results consistently show that quantum entanglement is real, even though it defies classical logic. This phenomenon is a cornerstone of quantum mechanics and continues to provoke both philosophical and practical exploration into the nature of reality itself. We will skip the philosophical ramifications and focus on the practical as of entanglement in military systems. Does Quantum Entanglement's disregard for time and space violate Einsteins law that you cant exceed the speed of light (even for information). Particle entanglement does not violate relativity because, although entangled particles show instantaneous correlations regardless of the distance between them, this "spooky action at a distance" cannot be used to transmit information faster than the speed of light. The outcomes of measurements on entangled particles are random, and while their results are correlated, no usable signal or influence is transferred between the particles in a way that would allow faster-than-light communication. This ensures that the principles of causality and the speed limit imposed by relativity are preserved. WHY DONT LARGE OBJECTS DISPLAY QUANTUM BEHAVIOR SOME FINAL THOUGHTS In this series of articles, TDM has chosen to use wave theory to describe quantum behavior. We like this approach because we can see waves in our reality and extrapolate QM behavior from there. This is the "Copenhagen Interpretation". We also like this interpretation as they dont get meta phyical or cosmological. There are other theories that also describe quantum behavior. How can this be ? Because there are often many different solutions to the same problem. For Instance say we want 5 coconuts. I say the solution is to add 3 coconuts plus 2 coconuts. You say , no its take seven coconuts and then subtract two coconuts. Both solutions are very different, but both valid. For the sake of completeness we will look at a few of the other contenders. The Copenhagen interpretation, Bohmian ( not Bohemian) mechanics, and the Many-Worlds interpretation are three competing explanations of the strange and counterintuitive behavior of quantum mechanics, especially the concept of wavefunction collapse and the role of measurement. Copenhagen Interpretation The Copenhagen interpretation, formulated in the 1920s by Niels Bohr and Werner Heisenberg, is perhaps the most widely taught view. According to this interpretation, a quantum system exists in a superposition of possible states, represented by a wavefunction, until it is observed or measured. When a measurement is made, the wavefunction "collapses," and the system randomly takes on a definite state. This view emphasizes the role of the observer in the process of measurement, introducing an element of indeterminacy or randomness into quantum mechanics. The Copenhagen interpretation accepts that quantum phenomena cannot always be visualized classically and that the probabilities governing quantum behavior reflect the limits of what can be known about a system. Bohmian Mechanics In contrast, Bohmian mechanics (or the de Broglie-Bohm theory) offers a deterministic explanation of quantum phenomena. Proposed by David Bohm in 1952, this interpretation introduces the concept of "hidden variables" to account for the behavior of quantum particles. In Bohmian mechanics, particles have well-defined positions and velocities at all times, and their motion is guided by a "pilot wave" described by the wavefunction. Basically the superpositioned particle "surfs" on this pilot wave. While the wavefunction evolves according to the Schrödinger equation, the hidden variables dictate specific outcomes, thus avoiding the randomness and indeterminacy of the Copenhagen interpretation. Bohmian mechanics provides a clear, particle-based view of quantum systems, although it is non-local, meaning that the behavior of particles at one location can be instantaneously influenced by distant particles (a feature consistent with quantum entanglement). Many-Worlds Interpretation The Many-Worlds interpretation (MWI), proposed by Hugh Everett in 1957, rejects the idea of wavefunction collapse altogether. In this interpretation, the wavefunction describes the entire universe, and when a quantum measurement occurs, all possible outcomes of the measurement actually happen—but in different branches of the universe. Each possible outcome exists in its own "world" or universe, so rather than collapsing into one outcome, the universe "splits" into multiple versions. In this interpretation, quantum mechanics is entirely deterministic: all possible outcomes occur, just in separate realities, and there is no special role for the observer. The Many-Worlds interpretation provides a way to avoid the randomness and observer-dependent collapse of the wavefunction, but it leads to the counterintuitive idea that there are countless parallel worlds, which we are unaware of. Here at TDM we are NOT a big fan of this theory. Determinism vs. Indeterminism One key contrast between these interpretations is the debate between determinism and indeterminism. Bohmian mechanics offers a deterministic view, where the outcome of quantum events is predetermined by hidden variables, albeit in a non-local way. The Copenhagen interpretation, by contrast, embraces indeterminism, suggesting that the outcomes of quantum measurements are fundamentally probabilistic and that randomness is inherent to nature. The Many-Worlds interpretation, like Bohmian mechanics, is also deterministic, though it posits that every possible outcome occurs in a different branch of reality. The Role of the Observer The role of the observer is central in the Copenhagen interpretation, as the act of observation is believed to cause the collapse of the wavefunction. In Bohmian mechanics, the observer has no special role; particles follow deterministic paths, and the observer simply reveals the predetermined outcome. Similarly, in the Many-Worlds interpretation, the observer doesn’t affect the quantum system by causing collapse but instead becomes entangled with the system, splitting into multiple versions along with the universe. In summary, while the Copenhagen interpretation emphasizes the randomness and the active role of measurement, Bohmian mechanics proposes a deterministic and particle-based explanation, and the Many-Worlds interpretation removes the idea of collapse entirely, leading to the existence of parallel universes. Each interpretation addresses the paradoxes of quantum mechanics in a fundamentally different way. Here at TDM we have chosen to use the Copenhagen Interpretation. This method allows QM to be intuitive in a probabilistic sense, and avoids the infinte parallel universes non sense. TO SUMMARIZE ... There are 4 critical features of QM we must understand. A) Particles are NOT waves, but we need waves to describe them. B) Some particle properties are quantized. These properties are : Energy,Charge,Spin,Angular Momentum, and Magnetic Moment C) Quantum systems have inherent uncertainty. There is no way around it. Embrace it. D) Quantum effects can ONLY be seen in the realm of the extemely tiny. We can now move on to the actual practical uses of QM in military systems. Next up, Quantum Cryptography. References Stephen Hawking & Leonard Mlodinow, The Grand Design, Bantam Books,2012 Jakob Schwictenburg, No-Nonsense Quantum Mechanics, No-Nonsense Books,2020