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Exceptional polynomials

This page gives examples of exceptional polynomials according to the definition in my paper Distance to the discriminant. They are all homogeneous polynomials in three variables and therefore their zero locus are algebraic curves in the projective plane. These polynomials maximize the distance to the discriminant for the Bombieri norm, among polynomials of the same norm. As a consequence (see the paper), they can all be written as sums of powers of linear forms in the directions which correspond to critical points of the polynomial on the unit sphere with the minimum absolute critical value.

This page presents two kinds of polynomials: exact ones and numerical approximations. The former are normalized to be at distance one to the discriminant, while the latter are normalized to have Bombieri norm 1. In both cases, we give two expressions:

We provide images of the zero locus curves that can be zoomed and dragged. The curve is projected onto a disc shown in light grey using the stereographic projection x , y , z x 1 + z , y 1 + z of the hemisphere z > 0 . We also highlight with a cross the critical points with the least critical absolute value on the unit sphere. These are the directions of the linear forms in the expression as a sum of linear forms to the power d.

Table of curves (see the lexicon below for explanation of the remarks)

Degree Topology Remark Nb. of
forms
dist ( P , Δ ) P P P 1 PGood

Lexicon

M curve
Algebraic curve with the maximum number of connected components for its degree: M = ( d - 1 ) ( d - 2 ) 2 + 1 .
M-k curve
Algebraic curve with M - k connected components (k below the maximum).
EM-k curve
Extremal M-k curve: no extra oval can be added without changing the relative position of the existing ovals or increasing the degree.
LM-k curve
Extremal M-k curve: no extra oval can be added locally without changing the relative position of the existing ovals. Locally means that the transformation is a deformation in the space of polynomials with the same degree using only one singular point which is not an isolated point of the curve.
Harnacks's M-curve
Refers to the 1876 construction of Harnack [Harnack 1876] reaching the maximum for any degree.
Hilberts's M-curve
Refers to the 1891 construction of Hilbert [Hilbert 1891] reaching the maximum with nests containing many ovals. The construction also gives the two EM-2 sextic curves presented on this page.
Gudkov's M-curve
Refers to the 1960s construction of Gudkov [Gudkov 1974] for the last missing sextic M-curve.

Bibliography

  1. A. Harnack
    “Über die Vieltheiligkeit der ebenen algebraischen Curven”
    Mathematische Annalen, 10 (1876), 189–199.
  2. D. Hilbert
    “Ueber die reellen Züge algebraischer Curven”
    Mathematische Annalen, 38 (1891), 115–138.
  3. D. A. Gudkov
    “The topology of real projective algebraic varieties”
    Russian Mathematical Surveys, 29 (1974), 3–79. (Earlier version exists in russian)

Exact polynomials

Degree 2, ⟨1⟩ (M curve) 🟢

P = x2+y2-z2 = x2+y2-z2 P = 3 P-P1 = 0 dist(P,Δ) = 1±0

Degree 3, ⟨J ∐ 1⟩ (M curve) 🟢

P = z-3x2-3y2+z2 = 5z33--3x+z36-3x+z36--3y+z36-3y+z36 P = 7 P-P1 = 0 dist(P,Δ) = 1±0

Degree 4, ⟨4⟩ (M curve) 🟢

P = -x+y+zx-y+zx+y-z6x+6y+6z-x2+y2+z22 = -13x-y43-13x+y43-13x-z43-13x+z43-13y-z43-13y+z43+31x-y-z412+31x-y+z412+31x+y-z412+31x+y+z412 P = 197 P-P1 = 0 dist(P,Δ) = 1±0

Degree 4, ⟨3⟩ (M-1 curve) 🟢

P = -x+y+zx-y+zx+y-z2x+2y+2z+x2+y2+z22 = -3x4-3y4-3z4+x-y42+x+y42+x-z42+x+z42+y-z42+y+z42 P = 21 P-P1 = 0 dist(P,Δ) = 1±0

Degree 6, ⟨10⟩ V1 (LM-1 curve) 🟢

This is a M-1 curve, but locally extremal. It is probably not in the same rigid isotopy class than the next one.

P = -x2+y2+z23+2-xφ+2+z5+3+1φxφ+2+z5+3+1φx5+3+1φ-yφ+2x5+3+1φ+yφ+2y5+3+1φ-zφ+2y5+3+1φ+zφ+2-3φ+23+35+3+1φ333φ+23+35+3+1φ33 = 127-φx+zφ630+127φx+zφ630+127-φy+xφ630+127φy+xφ630+127-φz+yφ630+127φz+yφ630+127x-y-z630+127x-y+z630+127x+y-z630+127x+y+z630-21920-73515x61+56+y61+56+z61+56+-φx-yφ+1+z6+-φx+yφ+1+z6+φx-yφ+1+z6+φx+yφ+1+z6+-φy+x-zφ+16+-φy+x+zφ+16+φy+x-zφ+16+φy+x+zφ+16+-φz-xφ+1+y6+-φz+xφ+1+y6+φz-xφ+1+y6+φz+xφ+1+y6 P = 2311 P-P1 = 0 dist(P,Δ) = 1±0

Degree 6, ⟨10⟩ V2 (LM-1 curve) 🟢

This is a M-1 curve, but locally extremal. It is probably not in the same rigid isotopy class than the previous one.

P = 1458-4x29-4y29+5z29-4x29+5y29-4z295x29-4y29-4z29+x2+y2+z23 = -92362x2-2y263-92362x2+2y263-92362x2-2z263-92362x2+2z263-92362y2-2z263-92362y2+2z263+15255x3-2y3-2z364+15255x3-2y3+2z364+15255x3+2y3-2z364+15255x3+2y3+2z364+152552x3-2y3-z364+152552x3-2y3+z364+152552x3-y3-2z364+152552x3-y3+2z364+152552x3+y3-2z364+152552x3+y3+2z364+152552x3+2y3-z364+152552x3+2y3+z364-67443x3-3y3-3z36-67443x3-3y3+3z36-67443x3+3y3-3z36-67443x3+3y3+3z36 P = 91213 P-P1 = 0 dist(P,Δ) = 1±0

Approximated polynomials

Degree 5, ⟨𝐽 ∐ 6⟩ (Harnack's M-curve) 🟢

P = -0.00106873415699291x5+0.0298190870015163x4y+0.0298190870015163x4z-0.0965192797742039x3y2+0.53131622091545x3yz-0.0965192797742039x3z2-0.0965192797742039x2y3-3.08382139247772x2y2z-3.08382139247772x2yz2-0.0965192797742039x2z3+0.0298190870015163xy4+0.53131622091545xy3z-3.08382139247772xy2z2+0.53131622091545xyz3+0.0298190870015163xz4-0.00106873415699291y5+0.0298190870015163y4z-0.0965192797742039y3z2-0.0965192797742039y2z3+0.0298190870015163yz4-0.00106873415699291z5 19.0067688827383566386-x+0.060149842239871802922y-0.403906402377617521231z5-4.10506254927064870458-x+0.151988408912245202572y-z5+19.0067688827383566386-0.403906402377617521231x-y+0.060149842239871802922z5+19.0067688827383566386-0.403906402377617521231x+0.060149842239871802922y-z5+4.10506254927064870458-0.151988408912245202572x+y+z5-19.0067688827383566386-0.060149842239871802922x+0.403906402377617521231y+z5-19.0067688827383566386-0.060149842239871802922x+y+0.403906402377617521231z5-11.2705241276892411097-0.0407005400461146206818x-0.0407005400461146206818y+z5+11.27052412768924110970.0407005400461146206818x-y+0.0407005400461146206818z5+41.4816247609779069610.0740590551607518339134x+0.0740590551607518339134y+z5+41.4816247609779069610.0740590551607518339134x+y+0.0740590551607518339134z5-11.2705241276892411097x-0.0407005400461146206818y-0.0407005400461146206818z5+41.481624760977906961x+0.0740590551607518339134y+0.0740590551607518339134z5-19.0067688827383566386x+0.403906402377617521231y-0.060149842239871802922z5+4.10506254927064870458x+y-0.151988408912245202572z5 P = 1.0 P-P1 = 6.59982960231662876817·10-18 dist(P,Δ) = 0.0024915028190241140454±2.1·10-18

Degree 5, ⟨𝐽 ∐ 5⟩ (M-1 curve) 🟢

P = 0.138282576385407x5+1.60664479990138·10-74x4y+0.587838979474442x4z-1.38282576385407x3y2-3.45958159975304·10-74x3yz-2.46107002700762·10-16x3z2+1.47505838426774·10-74x2y3+1.17567795894888x2y2z-3.70217191641533·10-75x2yz2-1.09348571906146x2z3+0.691412881927033xy4-2.47113823740793·10-74xy3z-2.46107002700755·10-16xy2z2+2.7937426435764·10-74xyz3+2.09231774897847·10-16xz4-4.55162698598173·10-75y5+0.587838979474442y4z+2.22806310010669·10-75y3z2-1.09348571906146y2z3+2.12423438761526·10-75yz4+0.520200768721775z5 -0.29605504806173057544-x-0.72654252800536085922y-0.53504137204818599689z5-0.71454566055256360844-0.91062288684363371968x-3.607937568104080216·10-75y-z5+0.62348654107263842188-0.8606112651663603633x-0.62527068422385940514y-z5+0.62348654107263842188-0.8606112651663603633x+0.62527068422385940514y-z5+0.71454566055256397067-0.73670939092327428073x-0.53525070328668537012y+z5-0.66085414860515297247-0.32491969623290630207x-y+0.98842629975056749903z5-0.66085414860515297247-0.32491969623290630207x+y+0.98842629975056749903z5-0.71454566055256373042-0.28139794750145754851x-0.86605383042014205249y-z5+0.714545660552563730420.28139794750145754851x-0.86605383042014205249y+z5-0.664684995936653778350.32491969623290631514x-y-0.45513337563457402094z5-0.664684995936653778350.32491969623290631514x+y-0.45513337563457402094z5-0.714545660552563970670.73670939092327428073x-0.53525070328668537012y-z5+0.29605504806173057544x-0.72654252800536085922y+0.53504137204818599689z5+0.84932516656440315741x+6.8750384056112487783·10-75y-0.94004927325528403985z5-0.85424854497517219184x+8.1446624204447317375·10-75y-0.43285756268067151253z5 P = 1.0 P-P1 = 1.2899195370252784891·10-16 dist(P,Δ) = 0.023035530697453850865±2.0·10-17

Degree 6, ⟨9 ∐ 1⟨1⟩⟩ (Harnack's M-curve) 🟢

P = 9.61142335107702·10-5x6+3.94443008515037·10-10x5y+2.67267233665759·10-10x5z+1.89115375851639x4y2+2.58331622515706x4yz+0.875510022522388x4z2+2.66999394915689·10-10x3y3-6.20517332800208·10-10x3y2z-2.05949268851703·10-9x3yz2-9.31641981873725·10-10x3z3-1.26028860154197x2y4+1.7222108157218x2y3z+1.75102004537569x2y2z2-1.04016485661514x2yz3-0.646445147783245x2z4-1.32826799302121·10-10xy5+6.55961777153812·10-10xy4z-3.68042052082951·10-10xy3z2-9.32752465572185·10-10xy2z3+3.18455509933182·10-10xyz4+1.98003078320781·10-10xz5+0.210192271668139y6-0.861105408365832y5z+0.875510021681553y4z2+0.346721619732493y3z3-0.646445147562636y2z4-1.37166228257369·10-10yz5+9.61142335107702·10-5z6 66.93686669425698903529-x-0.8218932677946685127487y+0.6112970526059105521734z6+29.83886372938646615504-x-0.5773502693407670262029y+0.7755416011207467205052z6-161.4834524074586203881-x-0.5773502693198680564291y+0.6680498092570660452873z6+211.9380952162161431169-x-0.3755455622667985054818y+0.5044618876121104498163z6+364.9834573493371747307-x-2.669008966417179101189·10-13y+1.530793450735262160484·10-10z6-310.3206708905372230308-x+0.1794164579134390463943y-0.2584626453433536742282z6-161.483452605925767409-x+0.5773502692010713005547y-0.6680498088140657390602z6+29.83886377195106663602-x+0.577350269202969934971y-0.7755416006302053481315z6-67.92753763377424356878-0.844215781348180053884x-y+0.3329343390973398906134z6+70.72915848987851912085-1.025471157509130158372·10-10x-y-0.6716387282567188091039z6-382.7755909860688652925-8.829686423469717273501·10-11x-y-0.5785481058127065480823z6+3.1833702276806626993571.530793450735540212018·10-10x-1.060454037763545767665·10-10y+z6+290.23761992057814214980.1658457998032896828955x-y-0.478708252551350989984z6+290.23761992073230845340.1658457999493018905309x+y+0.4787082525005334776673z6-236.50042264724359801780.3605824654230248522674x-y-0.2704337660992902758391z6-236.50042264751672701110.3605824655052172933009x+y+0.2704337659888427675485z6+153.97739606939559200180.5773502691892671343616x+y+1.766848541306840039539·10-11z6+153.97739606911086567690.5773502691899788700535x-y-1.94429287584244143221·10-10z6-67.927537633590576786740.8442157814510250374912x-y+0.332934338839025927607z6+66.93686676959816746622x-0.8218932676399535888585y+0.6112970521850770384516z6+211.9380954128682341349x-0.3755455622081881381574y+0.5044618872279388184746z6-310.3206707430237639868x+0.1794164579281873606829y-0.2584626456699894184131z6 P = 1.0 P-P1 = 3.701534591526215018437·10-16 dist(P,Δ) = 0.00009611423351077027294014±4.4·10-17

Degree 6, ⟨6 ∐ 1⟨2⟩⟩ (EM-2 curve) 🟢

P = 0.00589370417177452x6-0.00810722420831899x5y-0.10447541397529x5z-0.13246170003432x4y2+0.507503425686876x4yz+0.48496566263209x4z2-0.340529737547038x3y3+1.06649896955336x3y2z-4.25866713675959x3yz2-0.102094774223009x3z3-0.387024873194602x2y4+0.82973870683771x2y3z+6.87333566012994x2y2z2+0.500807048068058x2yz3-0.021632585240089x2z4-0.198554452044143xy5+1.15205593386011xy4z+1.04043383730238xy3z2+0.961863155460903xy2z3+0.157899579839491xyz4+0.000589006101698443xz5-0.0260996888277111y6+0.200758307624054y5z-0.0915693420332y4z2+0.169052103282536y3z3+0.0328301791661001y2z4+0.000389369942468445yz5-0.000247824170496405z6 87.66646864564133967407-x-0.1507293597227276952201y-0.1157839790016475252289z6+265.6957559909633296016-x+0.065650241518947071828y-0.0859866326669048964606z6-153.7999933798103593101-x+0.3279036352493385149154y-0.03357610317218884702966z6+56.51911811773487533917-x+0.7048539152754089039994y+0.002037252838309579270864z6-50.83277840913819544554-0.7755717129177099727248x+y+0.04441005916920915745317z6-124.6938202985261106282-0.2149458091187146144034x-0.3078411813492471006455y+z6+83.66722354267773963712-0.1954058467210668898676x+y+0.1191397881834638853994z6+127.02202342069828286-0.1951164913941355558577x+y+0.4034946388763416214009z6-107.2131512627209183429-0.1472917695691492199013x-0.02571699358497896138242y+z6+22.36546402489446321938-0.1292507806402819707198x+0.671894154008624656853y+z6+406.7913764011825171958-0.09415465369625705064322x-0.1364706990341131093822y+z6-121.2378219049532003115-0.0008313540981224980538622x-0.004069789319835573878709y+z6-106.98361176623674145350.02802591735275618142236x-0.1493366314922560001229y+z6-28.154235062873190011110.1751266439942546998774x-y-0.7963553267184028747649z6-301.31271603095386667990.2514791432050271865961x-y-0.1823871641707819966009z6+22.002985581663791896930.3299484396081005613924x+0.4709992882946424591097y-z6+160.64974805315798034490.4325505542742250263193x-y-0.09660458117281437004966z6+22.145418796938959149160.6800810289776988237387x+0.1023913279096786582978y+z6-353.1992244036750545862x+0.09638920334209254978348y+0.1750846373868174072439z6+133.6307590682774476811x+0.1503574351733348949438y+0.3976667330107091116902z6-28.63718263211169353803x+0.1692261177187930400198y+0.7917080778383553338454z6 P = 1.0 P-P1 = 8.970496853187705608646·10-16 dist(P,Δ) = 0.0002488484400222630224711±1.4·10-17

Degree 6, ⟨2 ∐ 1⟨6⟩⟩ (EM-2 curve) 🟡

P = -0.396663870421845x6+0.21640136821548x5y-0.0109419425863456x5z-0.817302526479211x4y2+0.480727148033585x4yz+1.27206642925114x4z2+0.0508999223953165x3y3-0.175349776021781x3y2z-0.451149966359067x3yz2+0.0232569761630186x3z3-0.163029808841434x2y4+1.04638338228826x2y3z+1.51195475956507x2y2z2-1.04470250583701x2yz3-1.35783369451186x2z4-0.234906246896497xy5-0.16662769621355xy4z+0.0221136877114046xy3z2+0.181835573825952xy2z3+0.235225289182254xyz4-0.0123739559359578xz5+0.194998705706449y6+0.566460762192212y5z-0.0075389028994482y4z2-1.13007440315571y3z3-0.670730783712748y2z4+0.566435465154484yz5+0.482446648620436z6 -17235.78104699570293473447-x-0.2851841792468901466164228y-0.9466525988899391577200791z6+5899.186159204703864722619-x-0.1537138956698187087281564y-0.9312014362521081371866965z6+11386.0057152624567782707-x+0.06854216572956906567952428y+0.9683731905951183589236783z6+15282.44910132815415039056-0.9548768722027601019074167x+0.3723098942956923570212882y+z6+8332.79310063802901769469-0.9524616191849832204727064x-0.6088550471512390858715661y-z6-12283.77805358791429886764-0.7738609928751662362447604x+0.6246203299665835452853354y+z6-7005.341876830503662653868-0.6889837205598905521157403x-0.8815560402753638775140902y-z6+17902.62673388210327959808-0.6691231242757296513154339x+0.6996944209205973014384501y-z6+10250.59896621212295068646-0.4826816020533194278651224x+0.854600981819704456623873y+z6-8637.513759236634518120618-0.1074991467068560466435651x+y+0.9985571075818118589669307z6+8228.0013586363063275406640.3006376799025245188684201x+y+0.9806010843155804926650267z6-1178.7115791374692310765190.4249775146433635344137617x-y+0.9217325980973065315506236z6+3450.5691908913880665180740.5069223619506646982646841x-0.9772348022780100016635431y+z6-9242.3624516910503894566190.5827266931497678686261168x-0.8368117392224609922490641y+z6-5161.0220786226231699891550.6585249967682479015943296x-0.682249366830989123122004y+z6-7176.854033540220423667760.771066115395020367890421x-0.5732827026747682488694338y+z6-24264.08468939870918547297x-0.1699662094439660390551409y-0.9706045077988005008011373z6+6651.727835992715249056793x-0.1176627272258781352437861y-0.9485086878956505224980934z6-2784.698770358048095086016x+0.001988443429663307070758101y-0.9833693350705429068603123z6+6426.084880811371644254234x+0.113795140982637392991505y+0.9509181896889256582375056z6 P = 1.0 P-P1 = 1.563486337576989874767171·10-11 dist(P,Δ) = 0.0000006564983740133337636567442±2.2·10-17

Degree 6, ⟨1 ∐ 1⟨9⟩⟩ (Hilbert's M curve) 🟢

P = -0.463676008413115x6+1.26390330377364·10-8x5y-4.63257086820353·10-7x5z-0.650659383368547x4y2+0.262615746075259x4yz+1.46209055277665x4z2-8.65065554707418·10-9x3y3-4.63703003390089·10-7x3y2z+1.38303903248024·10-7x3yz2+9.72574226759599·10-7x3z3-0.117427822291915x2y4+0.704813684540312x2y3z+1.66715542428863x2y2z2-0.445952509119675x2yz3-1.52545873396788x2z4-1.60444576368352·10-8xy5-7.21090619761633·10-8xy4z+2.24607818138239·10-7xy3z2+5.80365292711414·10-7xy2z3-1.2530094535893·10-7xyz4-5.06804485221378·10-7xz5+0.0855830564465105y6+0.405460169459421y5z+0.407757382820572y4z2-0.600021803746839y3z3-0.994311051098061y2z4+0.186036994408672yz5+0.527208683439629z6 1850555.33531871767872576778-0.987851014885905556112132088x-0.106139848843755440937596419y+z6-2374262.60452713702992949187-0.980532959723679492697858044x-0.260438506345591706450492045y+z6+574945.970085544882459069942-0.977062516154462552470284354x+0.30143858863936072045498432y-z6+1019052.94417849084735622131-0.967090225033569233549743316x+0.327324104803203692374806041y-z6-1494724.01187274258520413641-0.956483498679631273516771421x-0.132187301948753472369365336y-z6-251102.793085081304267999897-0.954196444521114759678632058x+0.368561915919026973492572624y-z6+1250246.14653578283951981878-0.848183630165365173823307262x+0.411728060938907547077948515y+z6-1080725.46149209752927984505-0.643485826161730270419067755x+0.675414091581846399692258685y+z6-1080726.14787067089074780741-0.643485624785716935678759652x-0.675413990329890005506787027y-z6+976119.653393515255634480123-0.349228101934146883553936377x-0.865220308762646925545633402y-z6-940224.5353108949769978537160.0000000606365882411177047991768419x-0.934658609081793445505550325y-z6-5257.98474576545719547991010.0000000686626322520361584348302571x+y-0.553685855372668448014504131z6+5465.534530579653440654695680.0000000690898645192630566318318138x+y-0.558880262824078914522898743z6+976119.3169427389730137193220.349228246480645719652314676x-0.865220374617217823073663835y-z6+1250247.193169699944344071250.848183366367290820176171714x+0.411727964268361509828039234y+z6-251102.5566028647204869557120.954196775835579215055329061x+0.36856192964203889893423908y-z6-1494722.600805735863482377090.956483807555469958027849788x-0.132187366980091253029061461y-z6+1019051.971491990737694976420.967090558515994396613033063x+0.327324112151395466322696239y-z6+574945.4156404688838482052880.977062851629009230847908183x+0.301438591902903056612236266y-z6-2374264.902264382296883271370.980532625027766375790344971x-0.260438509683555456262138873y+z6+1850557.139594602272016310550.987850684956087150871777874x-0.106139877279932824579427874y+z6 P = 1.0 P-P1 = 6.98840116117683748992644576·10-17 dist(P,Δ) = 5.82146442783478375870245282·10-9±2.6·10-17

Degree 6, ⟨5 ∐ 1⟨5⟩⟩ (Gudkov's M curve) 🟢

P = -0.00132990000822424y6-0.0616200461333061y50.707106781186547524400844362105x-0.707106781186547524400844362105z+0.00104567643964428y50.707106781186547524400844362105x+0.707106781186547524400844362105z+0.0423766780436503y40.707106781186547524400844362105x-0.707106781186547524400844362105z0.707106781186547524400844362105x+0.707106781186547524400844362105z-0.00223803203245656265329976974954y4x-z2+0.000244121531585367849579923382741y4x+z2+0.0285392824519227691903999755141y30.707106781186547524400844362105x-0.707106781186547524400844362105zx+z2-0.12925458496204814129448834592y30.707106781186547524400844362105x+0.707106781186547524400844362105zx-z2+0.000389754482938959525133847046016y3x-z3+0.000124842074475882852056131479617y3x+z3+0.0124919547764453464109096998163y20.707106781186547524400844362105x-0.707106781186547524400844362105zx+z3-0.00354416617249992576772138111049y20.707106781186547524400844362105x+0.707106781186547524400844362105zx-z3+0.00000242636930582478404659543119726y2x-z4+0.394230632890865184680961874619y2x-z2x+z2+0.00000440611823967971157599027992591y2x+z4+0.000427153819177914190023670482077y0.707106781186547524400844362105x-0.707106781186547524400844362105zx+z4+0.000189092943319493398627445523985y0.707106781186547524400844362105x+0.707106781186547524400844362105zx-z4-0.000000247042452224817412433703003204yx-z5-0.0165983876059155323147168928308yx-z3x+z2+0.172673791645410065331194659611yx-z2x+z3-0.0000000363005780728571624794169484397yx+z5-0.000001660471942840434456797327164610.707106781186547524400844362105x-0.707106781186547524400844362105zx+z5+0.00002253644368881751918447571242240.707106781186547524400844362105x+0.707106781186547524400844362105zx-z5-0.0000000161812343280988403633336293434x-z6-0.00515590206634466020202411939977x-z4x+z2+0.546067270146320171697595924343x-z3x+z3+0.00518676318548150563914056476733x-z2x+z4+6.84766574026006639940924253017·10-11x+z6 -167462140.321176701583652489132-x-0.0841817828027667998013392961308y+0.997485287857214101376916696201z6+55055739.9501972194156296177312-x+0.114364481107367551732842941469y-0.996212862730053857147131461678z6-8280847.7360865321364889243944-0.981637388246154630186503873753x-0.608825284266300590089525078996y-z6-70142245.4512914168820429031835-0.979707711316297963576049017957x-0.253739208032426041478352424778y+z6+1862150.55171690285025281278593-0.97900135498655133776371225856x-0.696336260628075677058575824432y-z6+38643974.7174452970042259593978-0.959486200702161240283936700576x-0.351627944323446397268378043049y+z6-16838923.7252090821141439953013-0.937663269997385300680537406413x-0.437809661375089231717735299376y+z6+4147402.57405932621001633301867-0.920482049980398491352772998286x-0.497097510591201133054486160271y+z6+21347925.56522209178144095912140.985538655028765658353322541713x+0.48252183183334366208273910617y+z6-43159828.91949935731143154038310.990012953172638185336852294883x+0.337758659905169118211280524351y+z6+111921653.0187604147259900863730.994346300208977238119674610775x+0.160049406947371112625592154293y-z6+74322732.02039058536170098778280.99438795537665266811902468899x+0.193089178153952863624172832055y+z6-113859450.9162179185693334953530.998242726986911135550978449745x+0.0641542699349463333893876386532y+z6-24090665.934844113584111080236x-0.146840460784293085682587852068y+0.992610038479574302394103475322z6+97398696.9951930851082333271693x-0.127664630869451728516467679197y+0.994391918381327075311969256048z6-223256453.985527753571557141228x-0.0988875479900851276194391345382y+0.996313881033065652189556837229z6+162547806.184808119971082792091x-0.0361740380194784057704085566612y+0.998602810810778317617163788778z6+26165484.2858941698483452614031x-0.00254821474123598904155948467865y-0.99464857619524777621020267677z6-105380059.313954612248478721823x+0.0130316203394396028769926166129y-0.994109953477023694216423270649z6-59617163.0160084518612508197032x+0.0242030510843510414704556666324y-0.993232004268181654090580090746z6+238909354.144697984766328907855x+0.0358420066614339162037169348755y-0.994282639841816167146782195051z6 P = 1.00000000000000015344142921732 P-P1 = 1.56879735402602020685295966417·10-16 dist(P,Δ) = 7.38323798474677818443979735078·10-11±8.0·10-21

Degree 7, ⟨𝐽 ∐ 15⟩ (Harnack's M curve) 🟢

P = -1.74415402874978·10-10x7+0.193985061996207x6y-0.0674698195570194x6z+1.47457241517702·10-8x5y2-3.34288587749802·10-8x5yz+1.01491178382314·10-8x5z2+3.19653872230425x4y3-0.537105063338043x4y2z-1.12612133763269x4yz2+0.322178912498801x4z3-6.16682520044354·10-8x3y4-2.28770197209962·10-7x3y3z+1.98897825628962·10-8x3y2z2+1.10575615971594·10-7x3yz3-3.04774765965544·10-8x3z4-0.412696946812073x2y5-2.87922246275859x2y4z-4.69434441310397x2y3z2+0.79744414055892x2y2z3+1.81877730525204x2yz4-0.487300026163997x2z5+3.89755112946603·10-9xy6+4.20794560514053·10-8xy5z+1.50063760088956·10-7xy4z2+1.73813500346809·10-7xy3z3-3.22693680864886·10-8xy2z4-7.91808693362777·10-8xyz5+2.17225891352177·10-8xz6+0.0132679769536452y7+0.187064674904409y6z+0.978383145670196y5z2+2.24737285428712y4z3+1.84740166166103y3z4-0.46881063416948y2z5-0.81032990850427yz6+0.222620135268147z7 737.583632249725877922106-x-0.7430393317874477789192y-0.8783032079440896723802z7-522.166745110871534332099-x-0.345201971887186757688792y-0.992400308938238450847721z7+13.5338736804438272108341-x-0.032544020329245999475341y+0.702663067722345839900194z7+1392.08351380700445739413-x+0.496890579078654594886053y+0.950997197283469082170708z7-737.583529677060280996719-x+0.743039351238252417263789y+0.878303244045156127144227z7+2712.37399705287891175064-0.810561602964861236527234x+0.347844590607047120409006y+z7-2776.33933459518796115043-0.571963633287207716347078x+y+0.350841178780400211176522z7-4023.11923601468166064837-0.558694059828629659752311x+0.344795883897282020108047y+z7-7031.52375360478748348248-0.355160749944217022218366x-y-0.112982103724865975264171z7+5877.09335304817717709326-0.278905248244801235366719x+0.347843056650947065641545y+z7+12224.3119313938492766935-0.192898240460801982842019x-y+0.0670226346514183292531303z7-17593.4136549058751564525-0.0754484589178065130048167x-y+0.19095631764005904426417z7+6816.4262086221959207539-1.01449680877731271488031·10-8x-0.349255322568968955579317y-z7+5486.17016256516551167844-2.00869668293423156226093·10-10x+y-0.272939103913952872448434z7+25906.5374312034528745542-1.01336532310860083546528·10-10x-y+0.240534781256189021570316z7-15.71689853154774618844063.78709129858557151628194·10-9x-y+0.657474836793920856895284z7-17593.41369847666066896270.0754484577636922460966513x-y+0.190956316165219462095674z7+12224.31200879503111320390.192898236847259869017996x-y+0.0670226309928145783016208z7+5877.093139031437648154810.278905269979036241087271x+0.347843057152659693078279y+z7-7031.523835577501757038770.355160742556181711798671x-y-0.112982110161238846998282z7-4023.11894254353357878730.558694085919739795318808x+0.344795884870542444061626y+z7-2776.339282471412144958460.571963646054381875496642x+y+0.350841169052981428518166z7+2712.373709998587695676250.810561635502876765418596x+0.347844592065160428261279y+z7-661.4843042156400923292880.878865467022532596709758x-y-0.682048508368015631468337z7+661.4842851330708089731370.878865488055371175762438x+y+0.682048494786057242573682z7+2379.420988293481977215240.973785922083014070403365x-0.379977871411113311314881y-z7-2379.420685767123833865050.973785960204145883455996x+0.379977873746494947744039y+z7-522.166671535363017454661x-0.345201983524998599589661y-0.992400347566657150202895z7+13.5338749076322683399112x-0.0325440245968627515113304y+0.702663039968101975813966z7+1392.08370936341937722393x+0.496890564417769086891484y+0.950997159546439708772479z7 P = 1.0 P-P1 = 9.3661690299577384587753·10-17 dist(P,Δ) = 0.00000238287955329906566192218±2.8·10-17

Degree 8, ⟨18 ∐ 1⟨3⟩⟩ (Harnack's M curve) 🟢

P = 3.42639808625191·10-8x8-5.20218194718691·10-9x7y-3.34927900961968·10-9x7z+2.14927084494929x6y2+2.76750793316963x6yz+0.890891344032204x6z2-8.7090761580403·10-9x5y3+1.99506657847714·10-8x5y2z+5.118016639116·10-8x5yz2+2.23976367917429·10-8x5z3+0.716423769876259x4y4+4.6125132170289x4y3z+1.14924961321223x4y2z2-3.52509693886025x4yz3-1.63800689164346x4z4-1.75990922440709·10-9x3y5-8.52627334429744·10-9x3y4z+4.80459271614805·10-8x3y3z2+3.33511890999359·10-8x3y2z3-3.73752474256241·10-8x3yz4-2.39056725244219·10-8x3z5-1.194039148444x2y6+0.922502623527613x2y5z+3.68829033047973x2y4z2-2.35006459612284x2y3z3-3.27601379108108x2y2z4+1.14917690065212x2yz5+1.02387845537451x2z6+1.74698495308752·10-9xy7-7.23401247549844·10-9xy6z-3.17088271888009·10-9xy5z2+2.62547268472772·10-8xy4z3-5.24450473680407·10-9xy3z4-2.39160381153039·10-8xy2z5+4.32834637838548·10-9xyz6+7.1086594668879·10-9xz7+0.23880789236505y8-0.922502642618129y7z+0.721621944432765y6z2+1.17503233171612y5z3-1.63800687629417y4z4-0.383058989845222y3z5+1.02387845225685y2z6+5.12029721743252·10-9yz7-0.215868035709408z8 -41092.753101152946135664631-x-0.78377816208381896545425688y+0.73965084069786299859205662z8+101688.20790401539286398679-x-0.51112945346182100011645246y+0.79558758477653398332032514z8+272236.89420214674728393621-x-0.26866765768780414913863019y+0.41818887756115697704011554z8+272236.89076910931133645488-x+0.2686676581158176183230246y-0.41818888198682753313923478z8-153180.37509889329580389426-x+0.40222910364351236450615708y-0.62747585878708633683521774z8+101688.20546442076818924378-x+0.51112945499913986400789293y-0.79558759092887005607543752z8+573.82086707385807197495238-0.91247685013667526444729847x+0.52681875750222005432955982y-z8+158964.06012228293637267103-0.57735026918661909382640946x+y+2.6918972126833281548672355·10-10z8-243453.63867355946852148606-0.41304212435818333218493726x+y+0.22113039066831765695352774z8+273020.24625132097104870222-0.26723098646731015913584743x+y+0.41803870815880216665364816z8-257616.79657405273269001908-0.14211761058350007712286153x+y+0.58799771807245375231205929z8-257616.79657273177327057023-0.14211760837342227664952697x-y-0.58799771860811310049052458z8+254650.19728016590324178957-0.05113178954334642829357377x+y+0.70933897257945121066257308z8+254650.19727969611471613688-0.051131786876160487588622976x-y-0.70933897277220140651781269z8+62474.945637616317852239657-1.4634015991045443396840104·10-9x+y+0.77826427910536737490115777z8-327499.460330211131156628681.4204809541986528049259963·10-9x-y-0.75547339842913188206890986z8+871.577734232901175439351871.78511270603536564397396·10-9x-y-0.9490930135373968937752746z8-20.096685599885822276730351.8849436086770641560948949·10-9x+0.75651455491123575518210028y-z8+273020.246248688588067163540.26723098489760975574256869x+y+0.41803870916582490776881038z8-243453.638669931378770678560.41304212353058060192301557x+y+0.22113039222444255390801505z8+158964.060118971581498839140.57735026919263243420661713x+y+2.4437652668362515602945954·10-9z8-20.0966860457293472237536040.65516081801184222361669681x+0.37825727437047294989026441y+z8-20.0966856489971239235183260.65516082339331728810350926x-0.37825727530683318645972632y-z8-71304.9522657959334786194230.76891747478018995264070886x-y+0.25781637885680186933046808z8-71304.952263817748810490350.76891747575842545799966033x+y-0.25781637596158723009903623z8+573.820851296898877426545480.91247685704154667331997448x+0.52681875930868684148433881y-z8+22606.251390899473160342848x-0.9986604666328049374294719y+0.57077150597894813267481413z8-41092.752184156171237602758x-0.78377816427460879780713969y+0.73965084652752889889957734z8+63398.411897559632777194184x-0.64759982251797063795020648y+0.84398946578576729645964656z8+19767.46316725915625831158x-0.57735027138875186166523813y+0.89866218219140255852657055z8-103622.87560667255350504408x-0.57735027132444016546814445y+0.87234553997136114343871012z8-426329.31707296075435436071x-0.13267026916534226112727953y+0.20617325123822298269600597z8+502404.93075161207419456861x-2.2550045585050086749380026·10-12y+1.8832376649071639317685996·10-9z8-426329.31972351766144087686x+0.13267026905772824209846286y-0.20617324731152118406435103z8-153180.37799729442944874343x+0.4022291026876555552377843y-0.62747585353651365246914212z8-103622.87833259402512686151x+0.57735026942144554479490381y-0.87234553333637658745334096z8+19767.463702940459802742603x+0.57735026942852971433156211y-0.89866217538080545153828046z8+63398.413511321174950951057x+0.64759982045293647284234237y-0.84398945933389796666359291z8+22606.251780504791963144767x+0.99866046447687993375220631y-0.57077150098285932219238387z8 P = 1.0 P-P1 = 7.1837734110860747196532771·10-17 dist(P,Δ) = 3.4263980859463065386598227·10-8±1.9·10-17

Degree 8, ⟨19⟩ (M-3 curve) 🟢

This curve has 43 quasi-critical points, but the rank of the corresponding family of 8th power of linear forms is only 41, hence the polynomial is written using only 41 independent 8th power of linear forms. The missing points appear clearly on the drawing.

P = 0.0495589143528351x8-0.00188018680131159x7y-0.000795119640932293x7z-0.98222967758031x6y2-0.512485805811381x6yz-0.387887731197622x6z2+0.0196278020389989x5y3+0.0177437997933578x5y2z+0.0131094554566617x5yz2+0.00388115481719391x5z3+4.81286215768501x4y4+4.37041111569147x4y3z+5.46367682835569x4y2z2+2.26805542914645x4yz3+0.96347855083981x4z4-0.0115396380424817x3y5-0.00891660576928047x3y4z-0.0238949884583324x3y3z2-0.0108324040428585x3y2z3-0.0125477647548797x3yz4-0.00487482221080735x3z5+0.245163497293747x2y6+3.32420020860353x2y5z-1.75134056243491x2y4z2+2.90577734180137x2y3z3-1.78664997060123x2y2z4-2.14515883780769x2yz5-0.882233333049585x2z6-0.000352126771039669xy7-0.00481778746941958xy6z-0.000622356910905359xy5z2-0.00303919507158106xy4z3+0.00499500693115176xy3z4-0.000908018084730323xy2z5+0.0030737225764952xyz6+0.00177576523890042xz7-0.000593764825451007y8+0.00802584243368985y7z+0.121879421524613y6z2-1.1278120374435y5z3+2.6700988140946y4z4-1.70424194371066y3z5-0.740965215107721y2z6+0.511633629359521yz7+0.262270902028137z8 1.390023128461474579-x-0.514864672901870670517y+0.694792149280820947404z8-5.76856376174915765797-x-0.367651952864542142082y+0.449029247862737071282z8+11.0189889580600322248-x-0.348221060805872479425y+0.162547771489192290354z8+5.28914333657159287355-x-0.0623240371443920724944y+0.863300220608303397447z8-13.6179238115978697977-x-0.0133017772624531407553y+0.580884258432679159669z8-12.9799982438379493272-x+0.0147305009770848275137y-0.57992073239483549944z8-15.0428544729854527006-x+0.286420392192215051987y+0.106533249699119379954z8-8.21674557054554787186-0.832142048755301378634x-0.0523334213113831989111y-z8-8.11552529248380784848-0.830832358180963667038x+0.053493992183472768816y+z8+3.43594288028844556097-0.693008211955235835485x-y+0.596367698528421295515z8+3.5179481547302908655-0.691321266081178478422x+y-0.595271246521781144432z8+9.12166752574641419074-0.627558131122870499815x-0.333099558503366360046y-z8+9.03462017052236159039-0.626063742643032917838x+0.33384616536963884814y+z8-6.80361606701100434313-0.42602969155936136302x+0.616319883065497222444y+z8-18.7234703598625914949-0.381994900341736507673x-y+0.317287446742690586326z8-18.9774784807734199622-0.380583277447180849589x+y-0.316835905923849674503z8+3.69781507743267734732-0.215922762999589999033x-0.895930219341788753721y-z8-5.50865556312886726439-0.0010471814359080330952x-y-0.904757201368224393515z8-100.113503296839096484-0.000708485063682819988933x-y+0.0238613644964277896563z8+33.92172233399165921460.000769903958928277064165x+y+0.144533490296711020538z8-8.86176596319690156150.000852723761545914622879x+y+0.371604143066634607299z8+5.011341191106551477870.000949962549676449763213x+y+0.638207955168146082825z8+52.13823969410482745850.160693766253681369832x-y+0.129247334735093325364z8+51.81194314964536087330.162071164685063605015x+y-0.129394992845831119458z8+3.679170756796844900810.213874391306113097406x-0.896098005017882744826y-z8-6.856063222581239975650.427775829028201283447x+0.615899406602238563444y+z8-0.1681580905507497749520.715322446548715959756x-0.372214115513973854825y+z8+2.193867912693696897420.828811689671995075658x+0.195574543656054599001y-z8+2.372007601801588790110.829761350398868711896x-0.19688275752418034993y+z8+0.07130412948267556668980.936821208170425277126x-0.570529403619022106307y+z8-0.980972440487592667718x-0.834524192744189608891y+0.869136844752565805157z8+1.32947040636650824212x-0.516419196823238992133y+0.694224511242661041957z8-5.07900564980871701715x-0.369160421308773292273y+0.448390027651836735607z8+10.5872881566921501478x-0.349788852778525302644y+0.161880319012975976822z8+2.53494813346077842487x-0.220157481488407112402y+0.590156923216909136977z8+15.583818312096740699x-0.159136773462445597936y-0.351210389544920435209z8+5.25385219757797448039x-0.0637244489218174766948y+0.862105839372452686507z8+15.2447221886636640524x+0.157625892024054788088y+0.350311493330204895941z8+3.25367506160861802164x+0.218748564203778468505y-0.590954896662565830591z8-15.1015917993935178387x+0.284846874561262385414y+0.10575208127168468563z8-0.953137039630366940463x+0.832621710691360088755y-0.869378162435763103742z8 P = 1.0 P-P1 = 1.37922513912681184877·10-16 dist(P,Δ) = 0.00069817037013123745928±1.2·10-17

Degree 9 ⟨J U 28⟩ (Harnack's M curve) 🔴

P = -6.47690131545843·10-14x9-0.000894699521756603x8y-0.000896140509912845x8z-3.09220644734732·10-10x7y2-5.66814054893491·10-10x7yz-2.57068972868567·10-10x7z2-1.51675134076296x6y3-4.20115750163369x6y2z-3.84483992258021x6yz2-1.16042305503365x6z3-2.98903753395465·10-11x5y4-6.37583262041529·10-10x5y3z+6.4130497948779·10-10x5y2z2+2.52686110460851·10-9x5yz3+1.27602721429944·10-9x5z4+1.51257607600666x4y5-1.40456782361952x4y4z-6.40806653727669x4y3z2+0.586067739569115x4y2z3+7.18995079268125x4yz4+3.11292954998475x4z5+1.22179986633867·10-10x3y6-2.1265510462967·10-10x3y5z-1.11937042997033·10-9x3y4z2+1.75169667221458·10-9x3y3z3+2.10856613962517·10-9x3y2z4-1.8126185907653·10-9x3yz5-1.38122584014615·10-9x3z6-0.504788491576338x2y7+2.32840040407918x2y6z-1.28161330874381x2y5z2-6.19282709927595x2y4z3+4.79330053000986x2y3z4+6.22585909895079x2y2z5-2.73630046153379x2yz6-2.0907856951756x2z7-2.61224068948139·10-11xy8+1.62398508872973·10-10xy7z-1.87125656101384·10-10xy6z2-5.99291736462113·10-10xy5z3+1.26840898132158·10-9xy4z4+2.08237515797689·10-10xy3z5-1.33685646372163·10-9xy2z6+1.30498729084796·10-10xyz7+1.79970366202169·10-10xz8+0.0563858433370229y9-0.467293133613127y8z+1.28161330741715y7z2-0.708496733216063y6z3-2.39665026294871y5z4+3.11292955057919y4z5+0.912100152380785y3z6-2.09078569526425y2z7+1.40425959287793·10-10yz8+0.00705483675959769z9 2380896.82519547-x-0.729258346206677y+0.727781732441915z9-6947676.05364025-x-0.619721382928701y+0.618725694861009z9+13220124.7356317-x-0.577350269174812y+0.584631971179082z9-9609406.44174142-x-0.536478908104933y+0.596825504671969z9+7241456.37737902-x-0.44310322926996y+0.643168848479633z9+6821.3739251457-x-0.268061626727725y+0.293770854043093z9+3112667.81040602-x-0.0695426730080776y+0.829962798402872z9+9609406.44632266-x+0.53647890810518y-0.596825504526279z9-13220124.7417725-x+0.577350269174157y-0.584631971033646z9+2603883.3093554-x+0.577350269182715y-0.576422665048878z9-2380896.82657527-x+0.729258346188698y-0.72778173227943z9+380834.337196557-x+0.96793336044347y-0.96637815793565z9-412.346899407536-x+0.999790222623675y-0.401245079295575z9+968264.399786432-0.702257600040002x-0.786872848026557y-z9+589843.548169065-0.673952454347285x-y+0.998446601453092z9-5671750.2421848-0.250560639046082x+y+0.715839869966238z9+15415801.7564314-0.106899414664023x+y+0.591377748152394z9+29862547.5844375-0.0312057953677463x-y-0.526178255824751z9-29862547.5845394-0.0312057953401219x+y+0.526178255826924z9-1175698.57508409-4.40385294436983·10-11x+y-0.998366122433211z9-48245839.5044969-1.26525246074838·10-11x-y-0.506306138757093z9+730564.473970961-1.04368097832507·10-11x-y-0.463005198034606z9-9502674.045003661.22366877958784·10-11x+y+0.499196671225386z9+15415801.75629010.106899414699384x+y+0.591377748145064z9-5671750.242053320.250560639096163x+y+0.715839869949062z9-6824.82600867320.267836764427584x-y-0.29375433989396z9+6824.826007992030.267836764437262x+y+0.293754339867268z9+982379.4693751890.329792330460547x+y-0.998393240386254z9-982379.4694588070.329792330545524x-y+0.998393240338582z9-1215553.365132850.488205894752592x-y-0.921365232844725z9+1215553.36506890.488205894826941x+y+0.921365232811234z9+589843.5482718550.67395245442239x-y+0.998446601355671z9+968264.4003015960.702257599914497x-0.786872847989835y-z9-1158522.633414020.867442699517211x-0.500818274816218y-z9+1158522.632608170.867442699672619x+0.500818274840943y+z9-6947676.05706318x-0.619721382923902y+0.618725694711667z9-200186.245600638x-0.57735026918748y+0.534632351471496z9+7241456.38116333x-0.443103229271273y+0.643168848331481z9-5243069.58284678x-0.285490253090748y+0.722118164843785z9+6821.37392682709x-0.268061626751556y+0.293770853921731z9+1292140.98634919x-0.207960989785132y-0.968447332350232z9+3112667.81254989x-0.0695426730240845y+0.829962798239425z9-1292140.98737471x+0.20796098974824y+0.968447332170496z9+5243069.57971777x+0.285490253085343y-0.722118164997361z9+2603883.30817163x+0.577350269182815y-0.57642266519353z9+200186.245510888x+0.57735026918518y-0.534632351612168z9+380834.336903811x+0.96793336049731y-0.966378158133954z9-412.346899225847x+0.999790222637554y-0.401245079429082z9 P = 1.0 P-P1 = 0.695106665257518 dist(P,Δ) = 2.4519823671465·10-10±3.3·10-14