gauge fixing problem in cubic superstring field theory
DESCRIPTION
Gauge Fixing Problem in Cubic Superstring Field Theory. Masaki Murata YITP based on work in progress with Taichiro Kugo, Maiko Kohriki, Hiroshi Kunitomo and Isao Kishimoto. 1. Introduction 2. Gauge Fixing of Ramond Field 3. Gauge Fixing of Neveu-Schwarz Field (incomplete) 4. Other topic - PowerPoint PPT PresentationTRANSCRIPT
Gauge Fixing Problem in Cubic Superstring Field Theory
Masaki MurataYITP
based on work in progress withTaichiro Kugo, Maiko Kohriki,
Hiroshi Kunitomo and Isao Kishimoto
1. Introduction2. Gauge Fixing of Ramond Field3. Gauge Fixing of Neveu-Schwarz Field (incomplete)4. Other topic5. Future directions
Oct. 22, 2010 at YITP, Kyoto
1. Introduction(SSFT)
Open Superstring Field Theories (SSFT)
1. Introduction(Motivation)
Our goal is
write down Siegel gauge action with kinetic operator L0 (F0)
take into account of interaction terms
Batalin-Vilkovisky (BV) formalism
1. Introduction (Batalin-Vilkovisky )
BV formalism with "Gauge-Fixed basis"
field anti-field
standard BV formalism
BV master equation
Boundary condition gauge invariant action
BV master equation
Boundary condition gauge fixed action
Definition of and are different
1. Introduction (BV for bosonic SFT)
:Ghost number constraint is relaxed.
BRST transformation:
Benefit of gauge-fixed basis : action satisfying master equation is same form as original
Siegel gauge
field anti-field
2. Gauge Fixing of Ramond (1)Kinetic term
Kernel of Y : Additional gauge symmetry[Kugo,Terao (1988)]
Projection operator removing kernel of Y :
picture changing operator
,
[Arefeva-Medvedev (1988)]
2. Gauge Fixing of Ramond (2)Projected field [Kazama-Neveu-Nicolai-West(1986)]
We can rewrite the action as
Relax ghost number constraint of
BV master equation
BRST transformation
[Sazdovic(1987)]
constrained field
2. Gauge Fixing of Ramond (3)
Siegel gauge :
we don't have Y0 !!
field anti-field
Variation of action
3. Gauge fixing of NS (PTY)
gauge
PTY projection operator
Propagator
[Preitschopf-Thorn-Yost(1990)],[Arefeva-Medvedev-Zubarev(1990)]
-2, 0-picture
We would like to
write down Siegel gauge action with kinetic operator L0 (F0)
is problematic : doesn’t have Klein-Gordon operator (second derivative)retracts (part of) world sheet
textend the worldsheet retract the worldsheet
3. Gauge fixing of NS (PTY)
We haven't succeeded yet.I will show our trials to explain where difficulties come form.
3. Gauge Fixing of NS1. Constructed another projection operator (1)
Ramond
NS
naive extension
We can show
3. Gauge Fixing of NSProjected field with
The computation is much complicated.
Ramond
Ramond
We couldn't find counterpartNS
3. Gauge Fixing of NS2.Construct another projection operator (2)
seems to be important
: difficult to find
We investigated another projection operatorso that we can find
We found one example by slightly modifying PTY's
3. Gauge Fixing of NS
We found
However,
kinetic operator does not contain
4. Another topic
We searched another candidate of picture changing operator with no divergence
modified cubic SSFT has divergence
Result : we proved uniqueness of X and Y
1. 2. (Virasoro) primary,3. commutes with BRST charge,
Strategy : construct operators satisfying following conditions
study operators with different picture number
5.Future directions1. Investigate gauge transformation at linearized level
By straightforwardly calculating , we can specify what gauge is possible.The components eliminated by might be identified as anti-fields. This will make the calculation of simpler.
The computation is much complicated.
original gauge transformation
5. Future directions2. “Minimal BRST-closed space”
minimal : the number of independent component is minimum
BRST-closed :
We want to construct the simpler projected state.
We want to construct simpler projected space as minimal BRST-closed space.
“minimal BRST-closed space”
messy
for example let us consider Ramond sector
5. Future directionsMinimal BRST-closed space for Ramond
Start line
Second step Close
projected space can be expressed as minimal space!!
5. Future directionsWe want to construct ``minimal space’’ for NS
Ramond NS``zero modes''
First step
?
These two formalisms can be related through anti-canonical transformation
5. Future directions2. “Minimal BRST-closed space”
V
Iterative construction :
we can express any state in terms of
minimal : the number of independent is minimum BRST-closed :