Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Breaking the quadratic barrier for 3-LCCs over the Reals   We prove that 3-query linear locally correctable codes over the Reals of
dimension $d$ require block length $n>d^{2+\lambda}$ for some fixed, positive
$\lambda >0$. Geometrically, this means that if $n$ vectors in $R^d$ are such
that each vector is spanned by a linear number of disjoint triples of others,
then it must be that $n > d^{2+\lambda}$. This improves the known quadratic
lower bounds (e.g. {KdW04, Wood07}). While a modest improvement, we expect that
the new techniques introduced in this work will be useful for further progress
on lower bounds of locally correctable and decodable codes with more than 2
queries, possibly over other fields as well.
  Our proof introduces several new ideas to existing lower bound techniques,
several of which work over every field. At a high level, our proof has two
parts, {\it clustering} and {\it random restriction}.
  The clustering step uses a powerful theorem of Barthe from convex geometry.
It can be used (after preprocessing our LCC to be {\it balanced}), to apply a
basis change (and rescaling) of the vectors, so that the resulting unit vectors
become {\it nearly isotropic}. This together with the fact that any LCC must
have many `correlated' pairs of points, lets us deduce that the vectors must
have a surprisingly strong geometric clustering, and hence also combinatorial
clustering with respect to the spanning triples.
  In the restriction step, we devise a new variant of the dimension reduction
technique used in previous lower bounds, which is able to take advantage of the
combinatorial clustering structure above. The analysis of our random projection
method reduces to a simple (weakly) random graph process, and works over any
field.

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The categories of this paper are: hep-ph
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The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
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The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
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The categories of this paper are: q-bio
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The categories of this paper are: adap-org
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The categories of this paper are: bayes-an
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The categories of this paper are: acc-phys
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The categories of this paper are: econ
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The categories of this paper are: nucl-th