No-Cloning Theorem
The No-Cloning Theorem is a fundamental principle of quantum mechanics that states: It is impossible to create an exact copy of an arbitrary unknown quantum state. In simple terms, you….
Tag: no-cloning theorem
Quantum Information Disturbance Trade-off
In classical physics, if you want to know about a system—like measuring a car’s speed or temperature—you can simply observe it. The act of measuring doesn’t significantly affect the car….
Quantum Repeaters
Quantum repeaters are critical components in long-distance quantum communication systems. They play a similar role to classical repeaters in fiber-optic networks, but with a key difference: they are designed to….
Quantum Teleportation
Quantum teleportation is one of the most fascinating phenomena in quantum mechanics. Despite the science-fiction name, it doesn’t involve transporting matter or people from one place to another. Instead, it….
Quantum Digital Signatures
Quantum Digital Signatures (QDS) are the quantum analog of traditional digital signatures used in classical cryptography. Their primary purpose is to: Just like pen-and-ink signatures prove authorship, digital signatures prove….
Quantum Oblivious Transfer
Quantum Oblivious Transfer (QOT) is a powerful cryptographic protocol rooted in quantum mechanics. It allows a sender (let’s say Alice) to send information to a receiver (Bob) in a special….
E91 Protocol
The E91 Protocol is a Quantum Key Distribution (QKD) method proposed by physicist Artur Ekert in 1991. It was a significant development in quantum cryptography because it uses quantum entanglement….
Quantum Key Distribution (QKD)
Quantum Key Distribution (QKD) is a method of securely sharing secret keys between two parties using the principles of quantum mechanics. It allows two people—commonly called Alice and Bob—to communicate….
Quantum Information Theory
1. What Is Information Theory? Before diving into the quantum part, let’s first understand the classical version. Information Theory, developed by Claude Shannon, is all about: In short, it answers:….