<script type="text/javascript">
<!--
document.write('<div id="oa_widget"></div>');
document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=undefined&type=result"></script>');
-->
</script>
doi: 10.1007/bf01214748
Let A be a central simple algebra over a field F of characteristic not equal to two. It is proved that zero is a non-trivial sum of squares in A if and only if the trace form of A over F is weakly isotropic. This confirms a recent conjecture of Leep, Shapiro and Wadsworth.
510.mathematics, Division rings and semisimple Artin rings, Finite rings and finite-dimensional associative algebras, Fields related with sums of squares (formally real fields, Pythagorean fields, etc.), sum of squares, trace form, Skew fields, division rings, Quadratic forms over general fields, central simple algebra, Article
510.mathematics, Division rings and semisimple Artin rings, Finite rings and finite-dimensional associative algebras, Fields related with sums of squares (formally real fields, Pythagorean fields, etc.), sum of squares, trace form, Skew fields, division rings, Quadratic forms over general fields, central simple algebra, Article
citations This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 4 | |
popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Average | |
impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |