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In 1995 this analysis was successfully applied by Grassmann, G. Bellettini and M. Cobal and the top quark was observed in the data of the Tevatron collider. Later, the analysis was repeated on a larger data sample, confirming the results obtained in 1994.<ref>{{cite web|url=http://prola.aps.org/abstract/PRD/v52/i5/pR2605_1|title=Identification of Top Quark using kinematic variables|accessdate=2009-02-10|author=F.Abe et al.}}</ref>
In 1995 this analysis was successfully applied by Grassmann, G. Bellettini and M. Cobal and the top quark was observed in the data of the Tevatron collider. Later, the analysis was repeated on a larger data sample, confirming the results obtained in 1994.<ref>{{cite web|url=http://prola.aps.org/abstract/PRD/v52/i5/pR2605_1|title=Identification of Top Quark using kinematic variables|accessdate=2009-02-10|author=F.Abe et al.}}</ref>


After the top discovery Grassmann began to work on a connection between the classic [[theory of information]] ([[Shannon]], [[Chaitin]], [[Kolmogorov]] et al.) and physics.<ref>{{cite web|url=http://www.isomorph.it/letters/available-articles/resolveUid/fa69f10e1aacdcd3d4cc1f09f70bfb7f|title=On the mathematical structure of messages and message processing systems|accessdate=2009-02-10|author=H. Grassmann}}</ref> From the work done by [[Szilard]] (and also [[Landauer]] and [[Bennet]]) it is known, that there must be some sort of connection between physics and information theory, because storing or deleting one bit of information is in certain situations dissipating energy.<ref>Szilárd L., "Über die Entropieverminderung in einem thermodynamischen System bei Eingriffen intelligenter Wesen". Zeitschrift für Physik 1929; 53: 840-856, Berlin (Habilitationsschrift)</ref> <ref>R. Landauer, "Irreversibility and heat generation in the computing process," IBM Journal of Research and Development, vol. 5, pp. 183-191, 1961.</ref> <ref>C. H. Bennett, "The Thermodynamics of Computation -- A Review," International Journal of Theoretical Physics, vol. 21, no. 12, pp. 905-940, 1982.</ref> In spite of this fact neither classic information theory nor algorithmic information theory contain any physics variables ( the variable “entropy” used in information theory is not a state function and is therefore not the thermodynamic entropy used in physics). Grassmann tried to make use of existing and established concepts like “message”, “amount of information” or “complexity”, but setting them into a new mathematical frame work: his approach is based on vector algebra or on Boolean algebra instead of probability theory.
After the top discovery Grassmann began to work on a connection between the classic [[Information Theory]] ([[Cluade Shannon|Shannon]], [[Chaitin]], [[Kolmogorov]] et al.) and physics.<ref>{{cite web|url=http://www.isomorph.it/letters/available-articles/resolveUid/fa69f10e1aacdcd3d4cc1f09f70bfb7f|title=On the mathematical structure of messages and message processing systems|accessdate=2009-02-10|author=H. Grassmann}}</ref> From the work done by [[Szilard]] (and also [[Landauer]] and [[Bennet]]) it is known, that there must be some sort of connection between physics and information theory, because storing or deleting one bit of information is in certain situations dissipating energy.<ref>Szilárd L., "Über die Entropieverminderung in einem thermodynamischen System bei Eingriffen intelligenter Wesen". Zeitschrift für Physik 1929; 53: 840-856, Berlin (Habilitationsschrift)</ref> <ref>R. Landauer, "Irreversibility and heat generation in the computing process," IBM Journal of Research and Development, vol. 5, pp. 183-191, 1961.</ref> <ref>C. H. Bennett, "The Thermodynamics of Computation -- A Review," International Journal of Theoretical Physics, vol. 21, no. 12, pp. 905-940, 1982.</ref> In spite of this fact neither classic information theory nor algorithmic information theory contain any physics variables ( the variable “entropy” used in information theory is not a state function and is therefore not the thermodynamic entropy used in physics). Grassmann tried to make use of existing and established concepts like “message”, “amount of information” or “complexity”, but setting them into a new mathematical frame work: his approach is based on vector algebra or on Boolean algebra instead of probability theory.


In parallel to these studies he develops a new physics approach for studying shrouded wind turbines.<ref>{{cite web|url=http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V4S-44R2ND5-1&_user=3718927&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000061208&_version=1&_urlVersion=0&_userid=3718927&md5=78b50edc9c028e30a2734b59a5c2773b|title=Upgrading conventional wind turbines |accessdate=2009-02-10|author=F. Bet, H. Grassmann}}</ref>
In parallel to these studies he develops a new physics approach for studying shrouded wind turbines.<ref>{{cite web|url=http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V4S-44R2ND5-1&_user=3718927&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000061208&_version=1&_urlVersion=0&_userid=3718927&md5=78b50edc9c028e30a2734b59a5c2773b|title=Upgrading conventional wind turbines |accessdate=2009-02-10|author=F. Bet, H. Grassmann}}</ref>

Revision as of 10:33, 21 May 2009

Hans Grassmann (* May 21 1960 in Bamberg) is a German physicist who teaches and works in Italy. Grassmann is author of 4 books and more then 250 scientific publications, and is founder and director of the spin-off company Isomorph srl. His major contributions to physics are: the development of a CsI(Tl) calorimeter with photodiode readout, the W-charge asymmetry analysis, his contribution to the discovery of the top quark, the development of a physics theory of information, a new physics approach in the understanding of shrouded turbines and the development of a simple concentrating mirror system (“linear mirror”).

Life and Work

Study of physics

From 1979 to 1984 Grassmann studied physics at the Universities of Erlangen and Hamburg. For his laurea thesis he develops together with his supervisor E.Lorenz (MPI Munich) a new method for the calorimetric detection of high energy photons, based on the use of scintillating crystals (CsI(Tl)) with photodiode readout. Some of the most advanced scientific experiments have by now made use on this technology, for instance the Crystal-Barrel, the BaBar, the CLEO and the Belle experiments and the satellite Glast.

From 1984 to 1988 Grassmann was part of the experiment UA1 headed by Carlo Rubbia at the European centre for nuclear research CERN (Geneva), where he wrote his PhD thesis with H.Faissner (RWTH Aachen).

From 1987 to 1999 Grassmann was part of the CDF collaboration (Fermilab, Chicago) at the Tevatron collider, also working with the SSC lab (Superconducting Super Collider) at Dallas. In 1988 he developed with his student S. Leone the study of the asymmetry in the production and decay of the W-boson at the Tevatron proton-antiproton collider. At the Tevatron W particles are predominantly produced in collisions of valence quarks. Therefore one can determine the kinematic properties of the u- and d quarks (in the proton and antiproton) from the observation of W production. Furthermore, by analysing only the relative difference in the production of W+ and W- particles, one can substantially reduce the effects of systematic uncertainties in the experimental device.[1] [2]

In the following years Grassmann developed a new method for detecting the top quark.[3] The method makes use of the different kinematic properties of production and decay of top quark particles and of background events (like for instance the production of W particles together with hadronic jets).[4] In 1995 this analysis was successfully applied by Grassmann, G. Bellettini and M. Cobal and the top quark was observed in the data of the Tevatron collider. Later, the analysis was repeated on a larger data sample, confirming the results obtained in 1994.[5]

After the top discovery Grassmann began to work on a connection between the classic Information Theory (Shannon, Chaitin, Kolmogorov et al.) and physics.[6] From the work done by Szilard (and also Landauer and Bennet) it is known, that there must be some sort of connection between physics and information theory, because storing or deleting one bit of information is in certain situations dissipating energy.[7] [8] [9] In spite of this fact neither classic information theory nor algorithmic information theory contain any physics variables ( the variable “entropy” used in information theory is not a state function and is therefore not the thermodynamic entropy used in physics). Grassmann tried to make use of existing and established concepts like “message”, “amount of information” or “complexity”, but setting them into a new mathematical frame work: his approach is based on vector algebra or on Boolean algebra instead of probability theory.

In parallel to these studies he develops a new physics approach for studying shrouded wind turbines.[10] [11] [12] These studies are successful from a scientific point of view, and create several publications, but they do not directly lead to a new product due to a lack of funding.

Enterprenurship

The spin off company Isomorph focused instead on the development of an innovative concentrating mirror system aimed at making a more economic use of solar energy. Since the system is very simple, it would be cheap to produce.[13] [14] This "linear mirror" system received its first recognition from the Italian Physical Society in October 2008, when Alessandro Prest, a collaborator of Isomorph won a price for his presentation of the linear mirror.[15] The device became operational in autumn of 2008 and performed according to theoretical predictions. In 2004 the spin off company Isomorph srl is founded. From an economic point of view Isomorph has the mission to create new scientific concepts, procedures and devices, based on physics research and to sell those. From a scientific point of view Isomorph represents an attempt to make free research possible – research independent of the scientific-administrative complex.

Books

In books and newspaper articles Grassmann tries to explain physics to the general public. “Everybody can understand physics. What cannot be understood is not physics.” Each book is also dealing with some particular aspect of the relation between science and society. The books are also available in several translations.

  • Grassmann, H.: Das Top Quark, Picasso und Mercedes Benz – oder Was ist Physik?, Rowohlt Berlin, 1997, ISBN 3-87134-328-5.
  • Grassmann, H.: Alles Quark? Ein Physikbuch, Rowohlt Berlin, Berlin, 2000, ISBN 3-87134-362-5.
  • Grassmann, H.: Das Denken und seine Zukunft – von der Eigenart des Menschen, Hoffman und Campe, Hamburg, 2001, ISBN 3-455-09333-7.
  • Grassmann, H.: Ahnung von der Materie – Physik für alle., Dumont, 2008, ISBN 978-3832180829.

References

  1. ^ S. Leone. "Lepton charge asymmetry from W+- ---> lepton+- neutrino at the Tevatron collider". Retrieved 2009-02-10.
  2. ^ F. Abe; et al. "Lepton Asymmetry in W-boson decays from ppabr Collisions at sqrt(s)=1.8 TeV". Retrieved 2009-02-10. {{cite web}}: Explicit use of et al. in: |author= (help)
  3. ^ M. Cobal, H. Grassmann, S. Leone. "On exploiting the single-lepton event structure for the top search". Retrieved 2009-02-10.{{cite web}}: CS1 maint: multiple names: authors list (link)
  4. ^ M. Cobal, H. Grassmann, G. Bellettini. "Search for the top quark at CDF: Studying the structure of events with one lepton, a neutrino and jets". Retrieved 2009-02-10.{{cite web}}: CS1 maint: multiple names: authors list (link)
  5. ^ F.Abe; et al. "Identification of Top Quark using kinematic variables". Retrieved 2009-02-10. {{cite web}}: Explicit use of et al. in: |author= (help)
  6. ^ H. Grassmann. "On the mathematical structure of messages and message processing systems". Retrieved 2009-02-10.
  7. ^ Szilárd L., "Über die Entropieverminderung in einem thermodynamischen System bei Eingriffen intelligenter Wesen". Zeitschrift für Physik 1929; 53: 840-856, Berlin (Habilitationsschrift)
  8. ^ R. Landauer, "Irreversibility and heat generation in the computing process," IBM Journal of Research and Development, vol. 5, pp. 183-191, 1961.
  9. ^ C. H. Bennett, "The Thermodynamics of Computation -- A Review," International Journal of Theoretical Physics, vol. 21, no. 12, pp. 905-940, 1982.
  10. ^ F. Bet, H. Grassmann. "Upgrading conventional wind turbines". Retrieved 2009-02-10.
  11. ^ H. Grassmann, F. Bet, G. Cabras, M. Ceschia, D. Cobai and C. DelPapa. "A partially static turbine—first experimental results". Retrieved 2009-02-10.{{cite web}}: CS1 maint: multiple names: authors list (link)
  12. ^ H. Grassmann, F. Bet, M. Ceschia and M. L. Ganis. "On the physics of partially static turbines". Retrieved 2009-02-10.{{cite web}}: CS1 maint: multiple names: authors list (link)
  13. ^ Isomorph srl. "Measurement of the power transfer in a linear mirror with 20 mirror elements". Retrieved 2009-02-10.
  14. ^ A. Prest, H. Grassmann, "The linear mirror for solar energy exploitation", submitted to Nuovo Cimento Letters on 30-12-2008.
  15. ^ Società Italiana di Fisica. "Migliori comunicazioni 2008". Retrieved 2009-02-10.


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