News archive
to current news

Invited Talks 2015:

Invited seminar talk at MIT on 12 May 2015: MIT seminar

Earlier Invited Talks:

March 3 - 7, 2014: Nagoya (Japan), 5th Nagoya Winter Workshop on Quantum Information, Measurement, and Foundations

September 15 - 19, 2014: Castiglioncello (Italy), DICE 2014: Spacetime - Matter - Quantum Mechanics ... news on missing links

June 10 - 13, 2013: Växjö (Sweden), Quantum Theory: Advances and Problems
June 24 - 28, 2013: Moscow (Russia), Third International Conference on Theoretical Physics
July 29 - August 3, 2013: Prague (Czech Republic), Frontiers of Quantum and Mesoscopic Thermodynamics

June 11 - 14, 2012: Växjö (Sweden), Quantum Theory: Reconsideration of Foundations - 6
July 16 - 28, 2012: João Pessoa (Brazil), Advanced School on Quantum Foundations and Open Quantum Systems
September 17 - 21, 2012: Castiglioncello (Italy), DICE 2012: Spacetime - Matter - Quantum Mechanics from the Planck scale to emergent phenomena

Recent AINS paper (2012): "An Explanation of Interference Effects in the Double Slit Experiment: Classical Trajectories plus Ballistic Diffusion caused by Zero-Point Fluctuations ", Annals of Physics 327 (2012) 421-437, quant-ph/arXiv:1106.5994.

An explanation of interference effects in the double slit experiment is proposed. We claim that for every single "particle" a thermal context can be defined, which reflects its embedding within boundary conditions as given by the totality of arrangements in an experimental apparatus. To account for this context, we introduce a "path excitation field", which derives from the thermodynamics of the zero-point vacuum and which represents all possible paths a "particle" can take via thermal path fluctuations. The intensity distribution on a screen behind a double slit is calculated, as well as the corresponding trajectories and the probability density current. The trajectories are shown to obey a "no crossing" rule with respect to the central line, i.e., between the two slits and orthogonal to their connecting line. This agrees with the Bohmian interpretation, but appears here without the necessity of invoking the quantum potential.

Classical computer simulation of interference, with small 

Classical computer simulation of the interference pattern, Fig.1: intensity distribution with increasing intensity from white through yellow and orange, with trajectories (red) for two Gaussian slits, and with small dispersion (evolution from bottom to top; v(x,1) = -v(x,2)). The trajectories follow a "no crossing" rule: particles from the left slit stay on the left side and vice versa for the right slit. This feature is explained here by a sub-quantum build-up of kinetic (heat) energy acting as an emergent repellor along the symmetry line.

Classical computer simulation of interference, with large 

Classical computer simulation of the interference pattern, Fig.2: intensity distribution with increasing intensity from white through yellow and orange, with trajectories (red) for two Gaussian slits, and with large dispersion (evolution from bottom to top; v(x,1) = v(x,2) = 0). The interference hyperbolas for the maxima characterize the regions where the phase difference phi = 2n(pi), and those with the minima lie at phi = (2n + 1)(pi), n = 0,1,2,... Note in particular the “kinks” of trajectories moving from the center-oriented side of one relative maximum to cross over to join more central (relative) maxima. In our classical explanation of interference, a detailed "micro-causal" account of the corresponding kinematics can be given.

There are four AINS papers from 2010/2011. One is entitled: "Emergence and Collapse of Quantum Mechanical Superposition: Orthogonality of Reversible Dynamics and Irreversible Diffusion ", Physica A 389, 21 (2010) 4473-4484. See also quant-ph/arXiv:1004.4596.

Based on the modelling of quantum systems with the aid of (classical) non-equilibrium thermodynamics, both the emergence and the collapse of the superposition principle are understood within one and the same framework. Both are shown to depend in crucial ways on whether or not an average orthogonality is maintained between reversible Schrödinger dynamics and irreversible processes of diffusion. Moreover, said orthogonality is already in full operation when dealing with a single free Gaussian wave packet. In an application, the quantum mechanical “decay of the wave packet” is shown to simply result from sub-quantum diffusion with a specific diffusivity varying in time due to a particle’s changing thermal environment. The exact quantum mechanical trajectory distributions and the velocity field of the Gaussian wave packet, as well as Born’s rule, are thus all derived solely from classical physics.

Gaussian wave packet dispersion

Dispersion of a free Gaussian wave packet: Considering the particles of a source as oscillating “bouncers”, they can be shown to “heat up” their (generally non-local) environment in such a way that the particles leaving the source (and thus becoming “walkers”) are guided through the thus created thermal “landscape”. In the Figures, the classically simulated evolution of exemplary averaged trajectories is shown (i.e., averaged over many single trajectories of Brownian-type motions). These trajectories are thus no “real” trajectories, but they only represent the averaged behaviour of a statistical ensemble. The results are in full agreement with quantum theory, and in particular with Bohmian trajectories. This is so despite the fact that no quantum mechanics is used in the calculations (i.e., neither a quantum mechanical wave function, nor a guiding wave equation, nor a quantum potential), but purely classical physics.

The Figures display a simulation with coupled map lattices of classical diffusion and a time-dependent diffusivity. Two examples are shown, with different halfwidths of the initial Gaussian distribution, respectively: (1+1)-dimensional space-time diagrams (time axis from bottom to top), with the intensity field and nine exemplary averaged trajectories. In a, the initial half width is twice as large as in b. Note that the narrower the Gaussian distribution is concentrated initially around the central position, the more the thus “stored” heat energy tends to push trajectories apart.

The second paper (70 pages) is a review paper of our recent works, entitled
"Sub-Quantum Thermodynamics as a Basis of Emergent Quantum Mechanics", Entropy 12, 9 (2010) 1975-2044, in a Special Issue on Nonequilibrium Thermodynamics.

...and these are two papers from 2011:

"Elements of sub-quantum thermodynamics: quantum motion as ballistic diffusion", J. Phys.: Conf. Ser. (2011) 306 012046, doi: 10.1088/1742-6596/306/1/012046; based on a talk at the Fifth International Workshop DICE2010, Castiglioncello (Tuscany), September 13--17, 2010. See also quant-ph/arXiv:1005.1058.

"A Classical Explanation of Quantization", Found. Phys. 41, 9 (2011),1437-1453, doi: 10.1007/s10701-011-9556-1. See also quant-ph/arXiv:0812.3561.

to news archive

AINS paper entitled: "On the Thermodynamic Origin of the Quantum Potential", Physica A 388 (2009) 811-823.
See also quant-ph/arXiv:0808.3539.

Abstract: The quantum potential is shown to result from the presence of a subtle thermal vacuum energy distributed across the whole domain of an experimental setup. Explicitly, its form is demonstrated to be exactly identical to the heat distribution derived from the defining equation for classical diffusion-wave fields. For a single free particle path, this thermal energy does not significantly affect particle motion. However, in between different paths, or at interfaces, the accumulation-depletion law for diffusion waves provides an immediate new understanding of the quantum potential's main features.

Derivation of the Exact Schrödinger Equation

AINS-paper entitled "The Vacuum Fluctuation Theorem: Exact Schrödinger Equation via Nonequilibrium Thermodynamics" Phys. Lett. A 372 (2008) 4556-4563.
Abstract: By assuming that a particle of energy is actually a dissipative system maintained in a nonequilibrium steady state by a constant throughput of energy (heat flow), the exact Schroedinger equation is derived, both for conservative and nonconservative systems. Thereby, only universal properties of oscillators and nonequilibrium thermostatting are used, such that a maximal model independence of the hypothesised sub-quantum physics is guaranteed. It is claimed that this represents the shortest derivation of the Schroedinger equation from (modern) classical physics in the literature, and the only exact one, too. Moreover, a "vacuum fluctuation theorem" is presented, with particular emphasis on possible applications for a better understanding of quantum mechanical nonlocal effects.

Download the pdf-file

You may also want to read the sequel of this paper, i.e.: "Diffusion Waves in Sub-Quantum Thermodynamics: Resolution of Einstein's 'Particle-in-a-box' Objection". See quant-ph/arXiv:0806.4462.


International Heinz von Foerster Congress 2007

University of Vienna, 16 - 19 November 2007
More information:

Symposium (in German):


Symposium der Karl Popper Foundation an der Universität Klagenfurt, 14. - 15. Oktober 2005.

AINS-Beitrags: Was, wenn NICHTS die Welt im Innersten zusammenhält? download as pdf-file   


TIME AND HISTORY. 28th International Wittgenstein Symposium, 7. - 13. August 2005

Preliminary information


New Discussion Paper (in German)/ Diskussionspapier:

Gerhard Grössing, KONTINUUM. Die Geschichte einer Verdrängung, mit besonderem Augenmerk auf die Quantentheorie, OeZG 16, 1 (2005) 137 - 167.


English Abstract: "Continuum: A history of repression - with a special focus on quantum theory." download as pdf-file   

A New Derivation of the Schrödinger Equation (2004)

AINS-paper entitled "From Classical Hamiltonian Flow to Quantum Theory: Derivation of the Schrödinger Equation" published in Foundations of Physics Letters 17, 4 (2004) 343-362.

Abstract: It is shown how the essentials of quantum theory, i.e., the Schrödinger equation and the Heisenberg uncertainty relations, can be derived from classical physics. Next to the empirically grounded quantisation of energy and momentum, the only input is given by the assumption of fluctuations in energy and momentum to be added to the classical motion. Extending into the relativistic regime for spinless particles, this procedure leads also to a derivation of the Klein-Gordon equation. Comparing classical Hamiltonian flow with quantum theory, then, the essential difference is given by a vanishing divergence of the velocity of the probability current in the former, whereas the latter results from a much less stringent requirement, i.e., that only the average over fluctuations and positions of the average divergence be identical to zero.

quantum flow

Schematic distinction of classical Hamiltonian flow (left) and quantum flow (right), with the circles indicating the propagation of spherical Hamilton-Jacobi wave surfaces. The dotted lines (right) indicate symbolically that the waves pictured represent only the local surroundings of a generally extending undulatory probability field, thus illustrating that the fluctuations are to be seen in the context of the whole (nonlocal) environment.

download as pdf-file   

Discussion Paper (in German)/ Diskussionspapier:

Gerhard Grössing, WARUM ETWAS WIRD. Zur Selbstorganisation rekursiver Erprobungen im Möglichkeitsraum, OeZG 13, 3 (2002) 9 - 49.

download as pdf-file   

English Abstract: "Why Things Develop: On the Self-Organization of Recursive “Probes” in Possibility Space." download as pdf-file   

Comments welcome: / Kommentare erbeten an: ains[at]


Gerhard Grössing, "Zum Bilderstreit in der Quantentheorie"

Institut für Wissenschaft und Kunst Wien (, 10. Januar 2003, 18:30.

Zusammenfassung als pdf-file   

Cybernetics and Systems Vol. 32, No. 3-4 (2001):

Special Issue on "Time’s Arrow". A Festschrift on the Occasion of the 10th Anniversary of the Austrian Institute for Nonlinear Studies


G. Grössing (AINS), Preface

M. Jeitler (CERN), Time’s Arrow in Particle Physics

G. Grössing (AINS), Nonlocality and the Time-Ordering of Events

F. Benatti, R. Floreanini, and A. Lapel (Univ. Trieste, INFN), Open Quantum Systems and Complete Positivity

H. Rauch (Atominstitut, Vienna), Unavoidable Quantum Losses in Zeno-Like Neutron Experiments

M. Courbage (Univ. Paris), Time Operator in Quantum Mechanics and Some Stochastic Processes With Long Memory

C. C. Martin and R. Gordon (Univ. Saskatchewan, Univ. Manitoba), The Evolution of Perception

A. Riegler (Free Univ. Brussels), The Cognitive Ratchet

S. Fussy, G. Grössing, and H. Schwabl (AINS), Irreversibility in Models of Macroevolution

R. Gordon (Univ. Manitoba), Making Waves: the Paradigms of Developmental Biology and their Impact on Artificial Life and Embryonics


A Symposium as part of EMCSR 2000 - University of Vienna / Main Building, April 25 - 28, 2000.

Most of the fundamental laws in the natural sciences are formulated as time-symmetric ones, thereby reflecting the conception from classical dynamics of time as a mere parameter. A notable exception is the Second Law of thermodynamics, which introduces an arrow of time into physics. Although this law states that the entropy in a closed system can only remain constant or increase, but never decrease, its relation to other areas of the natural sciences has not been very clear.

In particular, there exist two areas "adjacent" to thermodynamics, which at first sight seem to largely oppose the Second Law, albeit for different reasons. On the one hand, quantum theory is characterized by time-symmetric fundamental equations (like the Schrödinger equation or some relativistic analogue thereof). On the other hand, biological evolution has recently been shown to exhibit features of time- symmetric "punctuated equilibrium" behavior. Still, evolution might generally have to be characterized by a progressive trend of increasing order. However, even this time-asymmetry apparently would be in opposition to the entropy law.

In this symposium, we intend to collect evidence for an arrow of time in the fields just mentioned, i. e., quantum theory and evolutionary biology. For, contrary to widespread belief, the solutions to the fundamental equations of quantum theory do show time irreversible behavior due to a breaking of their inherent symmetries. Similarly, irreversibility also characterizes laboratory experiments and computer models of biological evolution. So, we are confronted with the scenario that in both fields some fundamental laws may be time-symmetric, while any concrete systemic behavior generally is not, because it represents an emergent phenomenon.

Ideally, participants could compare the latter with more general (thermodynamic or other) considerations to enquire whether the concepts of irreversibility in the quantum and biological domains, respectively, are radically different, or whether they share common, perhaps basic, systemic characteristics.


Prof. Richard Gordon (Univ. of Manitoba):


(Invited lecture on the occasion of the 10th anniversary of AINS, Friday, April 28, 16:00 - 17:00, University of Vienna / Main Building)

Serious Matter: The John-Bell – Scandal

Abstract: In a festive lecture at the University of Vienna in 1987, on the occasion of Erwin Schrödinger’s 100th birthday, the famous physicist John Bell complained about the “scandal” (literally) that the so-called “deBroglie-Bohm interpretation” (BBI) of quantum theory was not taught at the universities and treated on an equal footing with the predominant “Copenhagen interpretation”. On the contrary, over decades, and up to the present day, the BBI has almost always been marginalized or grossly misrepresented by leading quantum physicists.

Actually, John Bell devoted practically all of his papers on quantum theory to the implications around the BBI, as can easily be seen from the collection of said papers in his book on “Speakable and Unspeakable in Quantum Mechanics”. Now, in November 2000, a symposium was held at the University of Vienna on the occasion of the 10th anniversary of Bell’s death. Physicists were invited to talk at this symposium who only recently had published utterly wrong “arguments” calling for the dismissal of the BBI. However, not a single exponent of the BBI was to give a talk, although the symposium was performed in the name of John Bell. Thus, the scandal is being prolonged.

Moreover, the series of (often provably intentional) misrepresentations of the BBI is continued in articles celebrating “100 years of quantum theory”….

Go to article written in December 2000: English version    Deutsche Version

ART & SCIENCE: Dialogprogramm im Haus Wittgenstein, März / April 1999

Programm: art & science

Contributions: museum in progress / art & science

Selbstdarstellung als Gestaltungsprinzip

Anmerkungen zu einer verqueren kunstgeschichtlichen Debatte über einen vermeintlichen mittelalterlichen Holzschnitt
...eine kurze Polemik zur "Wissenschaftlichkeit" in der Kunstgeschichte...

to current news