Quantum Computers Aren’t What You Think — They’re Cooler | Hartmut Neven | TED

Summary

Hartmut Neven, head of Google Quantum AI, reveals the potential of quantum computing, which operates on quantum physics rather than binary logic, offering immense computational power. He explains the concept of superposition and its application in quantum search algorithms, demonstrating the technology's ability to perform tasks in parallel universes. Neven also discusses current applications in quantum state preparation, like time crystals and non-abelian anyons, and the future of quantum computing in medicine, optimization, and even understanding consciousness, highlighting Google's progress in quantum error correction and the roadmap to a million-qubit computer.

Takeaways

• 💻 Hartmut leads Google Quantum AI and has been working on quantum computing since 2012.
• 🔄 Quantum computers replace binary logic with quantum physics, allowing for more powerful operations.
• 🌐 Quantum computing is based on the concept of a multiverse, farming out computations to parallel universes.
• 🪙 Superposition in quantum physics is key to understanding many-worlds theory and quantum computing.
• 🧠 Quantum mechanics suggests that objects, including humans, exist in a superposition of many configurations.
• 🔍 Quantum algorithms can perform certain computations more efficiently than classical computers, like searching through a large database.
• 📚 Hartmut demonstrates using Cirq, a Python-based language, to program quantum computers, which is akin to reading sheet music.
• 💡 Quantum computers today are used to prepare interesting quantum states and study their properties, leading to high-impact publications.
• 🧪 Quantum computing may enable new applications like detecting and analyzing molecules using nuclear electronic spin spectroscopy.
• 🔬 Google's roadmap for quantum computing includes building a computer with a million physical qubits, with progress already made on the first two milestones.
• 🚀 Quantum computers could revolutionize fields like medicine, battery design, and fusion reactors by simulating systems where quantum effects are crucial.

Q & A

What is the fundamental difference between classical computers and quantum computers?

Classical computers operate on binary logic of zeros and ones, while quantum computers replace this with the laws of quantum physics, allowing for more powerful operations and the ability to perform certain computations with fewer steps.

How does the concept of a 'multiverse' relate to quantum computing?

Quantum computing is the first technology that takes the idea of a multiverse seriously, where computations can be seen as being 'farmed out' to parallel universes, leveraging the concept of superposition in quantum physics.

What is the significance of 'superposition' in quantum physics and how does it apply to quantum computing?

Superposition is a key mathematical object in quantum physics that allows an object to exist in a superposition of many configurations simultaneously. In quantum computing, this principle enables the simultaneous exploration of many computational paths, leading to potential computational advantages.

Can you explain the analogy of the 'tall closet with a million drawers' in the context of quantum computing?

This analogy is used to illustrate the efficiency of quantum algorithms in search tasks. On average, it would take half a million steps to find an item in a classical scenario, but with a quantum algorithm, it could be reduced to just 1,000 steps.

What is the practical use of quantum computers today, according to the script?

Today, quantum computers are used to prepare interesting quantum states and study their properties, leading to numerous publications. They have also been used to create phenomena like tiny traversable wormholes, time crystals, and non-abelian anyons, which are helping to advance our understanding of quantum physics.

What is the significance of quantum error correction in the development of quantum computers?

Quantum error correction is crucial for the development of quantum computers because it helps to reduce the error rate of qubit operations. By combining many physical qubits into a logical qubit, the error rate can be significantly lowered, making computations more reliable.

What is Hartmut Neven's Law and how does it relate to the growth of quantum computing power?

Neven's Law states that the power of quantum computers will grow at a double exponential rate. This law is used to illustrate the dramatic increase in computational power that has been observed in quantum computers, with recent demonstrations showing computations that would take today's top supercomputers billions of years to perform.

What are some of the potential commercial applications of quantum computing mentioned in the script?

The script mentions the potential for quantum computing to enable new ways to detect and analyze molecules using nuclear electronic spin spectroscopy, which could lead to consumer applications like an 'electronic nose' in phones or smartwatches that can detect dangerous viruses or allergens in food.

What is the current status of the roadmap for building a large, error-corrected quantum computer?

The roadmap consists of six milestones, and two have already been achieved. The first milestone demonstrated a computation beyond the capabilities of classical computers, and the second milestone proved that quantum error correction is scalable technology.

How does quantum computing intersect with the field of neurobiology and consciousness?

The script suggests that quantum information science may help answer deep questions about the nature of consciousness, such as how it emerges from the multiverse. There is a program to experimentally test the conjecture that consciousness is the experience of a single classical world emerging from the many worlds of the multiverse, using quantum neurobiology methods.

What are some of the long-term applications of quantum computing that are being explored?

Long-term applications being explored include the simulation of systems where quantum effects are important, which could aid in designing more effective medicines, lighter and faster-charging batteries for electric vehicles, and hastening the design of fusion reactors to combat climate change. Additionally, a novel algorithm for optimization could impact various fields such as engineering, finance, and machine learning.