Entries by Arnold Neumaier

Vacuum Fluctuations in Experimental Practice

This Insight Article is a sequel of the Insight Articles ”The Physics of Virtual Particles”, “Misconceptions about Virtual Particles“ , and ”The Vacuum Fluctuation Myth”, which make precise what a virtual particle is, what being real means, document some of the liberties taken in physics textbooks in the use of this concept, mention the most […]

I am Professor for Computational Mathematics at the University of Vienna, Austria, with a strong interest in theoretical physics and its foundations.
I maintain the Theoretical Physics FAQ (http://www.mat.univie.ac.at/~neum/physfaq/physics-faq.html), a book-size collection of online articles on quantum mechanics and related topics, in the context of which I answer questions on PhysicsOverflow (http://www.physicsoverflow.org/).
My online book Classical and Quantum Mechanics via Lie algebras (http://lanl.arxiv.org/abs/0810.1019) presents quantum mechanics in very close analogy to classical mechanics. A revised version is scheduled to appear in print in 2017.

The Vacuum Fluctuation Myth

This Insight Article is a sequel of the Insight Articles ”The Physics of Virtual Particles” and “Misconceptions about Virtual Particles“ which make precise what a virtual particle is and what being real means, document some of the liberties taken in physics textbooks in the use of this concept, and mention the most prominent misuses. A further […]

I am Professor for Computational Mathematics at the University of Vienna, Austria, with a strong interest in theoretical physics and its foundations.
I maintain the Theoretical Physics FAQ (http://www.mat.univie.ac.at/~neum/physfaq/physics-faq.html), a book-size collection of online articles on quantum mechanics and related topics, in the context of which I answer questions on PhysicsOverflow (http://www.physicsoverflow.org/).
My online book Classical and Quantum Mechanics via Lie algebras (http://lanl.arxiv.org/abs/0810.1019) presents quantum mechanics in very close analogy to classical mechanics. A revised version is scheduled to appear in print in 2017.

Misconceptions about Virtual Particles

This Insight Article is a sequel of the Insight Article ”The Physics of Virtual Particles”, which contains an exposition of definitions that are physically justified, and in particular makes precise what a virtual particle is and what being real means. As discussed in detail in the companion article, virtual particles are defined as (intuitive imagery for) […]

I am Professor for Computational Mathematics at the University of Vienna, Austria, with a strong interest in theoretical physics and its foundations.
I maintain the Theoretical Physics FAQ (http://www.mat.univie.ac.at/~neum/physfaq/physics-faq.html), a book-size collection of online articles on quantum mechanics and related topics, in the context of which I answer questions on PhysicsOverflow (http://www.physicsoverflow.org/).
My online book Classical and Quantum Mechanics via Lie algebras (http://lanl.arxiv.org/abs/0810.1019) presents quantum mechanics in very close analogy to classical mechanics. A revised version is scheduled to appear in print in 2017.

The Physics of Virtual Particles

In discussions on the internet (including a number of wikipedia pages) and in books and articles for non-experts in particle physics, there is considerable confusion about various notions around the concept of particles of subatomic size, and in particular about the notion of a virtual particle. This is partly due to misunderstandings in the terminology used, […]

I am Professor for Computational Mathematics at the University of Vienna, Austria, with a strong interest in theoretical physics and its foundations.
I maintain the Theoretical Physics FAQ (http://www.mat.univie.ac.at/~neum/physfaq/physics-faq.html), a book-size collection of online articles on quantum mechanics and related topics, in the context of which I answer questions on PhysicsOverflow (http://www.physicsoverflow.org/).
My online book Classical and Quantum Mechanics via Lie algebras (http://lanl.arxiv.org/abs/0810.1019) presents quantum mechanics in very close analogy to classical mechanics. A revised version is scheduled to appear in print in 2017.

Causal Perturbation Theory

Relativistic quantum field theory is notorious for the occurrence of divergent expressions that must be renormalized by recipes that on first sight sound very arbitrary and counter intuitive. But it doesn’t have to be this way…. The basic building blocks of any quantum field theories are free fields that serve to define irreducible representations of the Poincare group with […]

I am Professor for Computational Mathematics at the University of Vienna, Austria, with a strong interest in theoretical physics and its foundations.
I maintain the Theoretical Physics FAQ (http://www.mat.univie.ac.at/~neum/physfaq/physics-faq.html), a book-size collection of online articles on quantum mechanics and related topics, in the context of which I answer questions on PhysicsOverflow (http://www.physicsoverflow.org/).
My online book Classical and Quantum Mechanics via Lie algebras (http://lanl.arxiv.org/abs/0810.1019) presents quantum mechanics in very close analogy to classical mechanics. A revised version is scheduled to appear in print in 2017.